Alright, here are the answers to your questions. I guess I need some vacation now after writing this novel.

If your question is not adressed here and wasn't answered by someone else in the meantime please drop me a line since I will have missed it.
Missing Percentages on Target/Implied Target windows: Haven't seen this on my system, but since the problem apparently began with 2.5.5 and I know what I changed in that version I suppose I can fix it in the next version.
Strange XP progression is caused by incorrectly rounded data that is delivered by SOE. The decimal is correct, but the integers are incorrect. The integers will not change while you gain in reality 2% XP. Since they are incorrectly rounded up, you will see 100% (displayed as 00%) although you really only have 98 or 99%.
molle65, the small zoning window allows you to chat while you're zoning, that's why it is there. If you don't like it, you can just delete the file
eq2ui_hud_zoning.xml from your ProfitUI directory.
Alkar, harvest information for all tiers is in the included InfoCenter from Milquetowst. Press the [?] button on the lower right start button/slider window to open it.
krisla, thanks for your kind feedback. I'll likely not put in the addon features that you proposed, since they are readily available from other authors (see post by
hiroprotagonist) and I know that a lot of people don't want them. Many people are asking for icons for food/drink but since you can easily drag them to a hotbar I don't see the point. I'll try to think of making queued spells more visible (if I find out how).
pox67,
casper you are not the first to report that the chat window cannot be moved. I was never able to reproduce this and I don't see why it wouldn't work for some. Maybe if one of you posted the .ini file of the toon this happens on I could check whether it is related to something in your setup.
Minnimowse, searching for specific sellers was re-enabled in one of the recent versions. It's working fine again.
nasuia, are you sure that you are seeing those channels in the 1280x1024 file? The 1024x768 and 1280x1024 files are the ones I provided and there are no channels defined therein at all. The .ini files for the other resolutions were contributed by users and are unfortunately not free of custom channels. Since my LCD screen can't do those resolutions I can't edit the files without messing them up. You can usually fix it yourself by doing /leavechannel X, for each channel number X that is predefined in the .ini and then log off. If you do that, please post the cleaned file here and I'll include that instead. And note that doing /load_uisettings will always keep your current channels even if the loaded .ini is clean. You'll need to manually replace the .ini files to have a completely clean setup.
Taldiira, see my response directly above for the channels. Quest rewards are showing fine AFAIK. I'll double check again with what the default UI shows. Group options are accessed by right clicking anywhere on the group window or player window except on yourself. Leave/Kick buttons are on the group window, a [x] will appear above the right end of each members health bar if you move your mouse there. Move your mouse around the group window, there are many further options.
As far as I know, the jump" of chat text you are seeing can't be related to the UI but seems to be a problem with the far seas req chat text. Thus, I'm pretty sure that the Default UI would have the same problem. I've never seen the text "jump" myself so far but I'll try to get a hold of the far seas req NPC in EL that you apparently spoke to and test it out. If you can resolve the issue by switching tabs it's probably not "game breaking" though.
Your last issue with the tabs in a group could indeed be caused by overlapping windows. There is no overlap in the default .ini on my system, but this game's broken UI engine gives a different representation for everybody so it might be different for you. Just move the group window a bit higher then, that should take care of it.
CobaltKnight, thanks for the bug report on the MyClass button if a Paladin. Will be fixed in the next version. I'll also work around the behaviour that the min. lvl displays ".000". Regarding the market window, the idea of having the buy and sell tabs both visible was already brought up and I agree that it would be nicer. However, I'm not sure yet how to implement it without making the window too large. Zonx has now changed his window in Fetish Nightfall that way that both are side by side. To do this he made everything really small, though, which I don't like too much. I'll think about a possiblity...
phyziks, I never heard of this problem and I don't see how it could happen. The UI cannot move anything to the overflow spot even if it tried to. Sorry, no idea in that case.
Sinlainu, very strange problem, since the code/font for all XP types is entirely identical. Maybe delete your complete ProfitUI folder (in the Program Files\Everquest II\UI directory) first and then reinstall. If that doesn't help, please tell me which version you had before that worked fine, and maybe a screenshot of the blurry dots would also help.
Pankratist,
odball69, the 1920x1200 file was contributed by
angelindisguise, since my screen doesn't support that resolution. The name of a maintained spell and it's remaining duration should always show. Maybe you need to enlarge the window to see it (hit F10 to see the size of the window)? Please let me know if that's the reason. And: If you come up with a better setup (or more like the default shown in my screenshots) just post it here and I'll be glad to include it instead or additionally.
Calare, my current understanding is that SOE broke the display of the target of a maintained spell with LU24. If you really are still seeing this on one character please let me know which server this is on, maybe that's the last "working" server for this.
Vanyari, the UI can't influence your shortcut keys. Hitting "r" for reply still works fine for me. Maybe you can reassign it in the options?
Brickabrac, hit "b" to open all bags (or whatever custom button you may have assigned to it - F12 for me, for example). The "show bank slots" option can't be hotkeyed unless you create your own macro in a hotbar for it. Put in the commands "bag_open -3 -50" and "bag_open -4 -51".
dew1960, Milquetowst InfoCenter is already included in ProfitUI. There is no way to access a spreadsheet from the game, however, and you cannot save information to external files from ingame.
Shainaen, the top left window is actually the experience window. You are right that there is some redundancy in windows, but this is to give flexibility to users. For example, you can resize your experience window to only show the top bar if you don't want the other/larger information. You could also remove the player window if you don't like it. Cure buttons are currently on the player and group windows. I'm pretty sure that most people would not like to have them on the experience window, which is very far away from your hotbars, i.e. from where the action is.
Droiyan7, this is actually how I have my XP window set up.

I still thought it would be easier for most to include the "frame & titlebar" option as well.
Anarissa, the flags for Epic mobs and the con frames are only available in con_version 1. You can switch con versions by clicking on the [x] that appears when you hover over the target window.
GnarDowg, if you use the sliders the settings cannot be saved. You can however select "frame & titlebar" in the windowsettings to permanently get larger icons (of a specific, non-selectable size).
t1ct4c, bags always opened like they do now by default. However, by changing the windowsettings to "none" or "frame" the bags will show vertical or horizontal.
ariven, is this the same issue that
Sinlainu described, i.e. is the achievement XP still displayed correctly and only the other XP types are wrong? Also, is the text in the titlebar still correct? (in that case I might have an idea of how to fix it...). A screenshot would be interesting. And if I can't fix it, sue nVidia.
RainQueen96, sorry about the bug with the AFK button.

Will be fixed in next release.