The same "dock window" trick should work at any level. If you're docking a sub page of inventory.inventory, just make a hidden dummy page at the same lvl pre sized and positioned to the smaller settings, then have your script set the values equal to the dummy page.
Example
Inventory
|_ Inventory
| |_Equipment
| |_Dock2
|_Dock1
Say your Equipment page is 200x300 and you want it to resize down to 100x200 and shoved into the lower right corner.
You'd set the Dock2 page to 100x200 and positioned into the lower right corner.
Your script would be something like...
Code:
OnPress="parent.Equipment.size=parent.Dock2.size parent.Equipment.location=parent.Dock2.location"
If you also wanted inventory.inventory to resize and reposition, you'd use the same method on Dock1, sizing and positioning it where how you want the inventory.inventory window to end up, then using similar script to make the transformation.