Please describe the problem:
The various controls in the Save Image dialog box are incorrectly positioned and the window itself is incorrectly sized.  In addition to looking bad, this presumably makes the two expandable items in the lower left side impossible or perhaps difficult to access (see attached image).  Note that this only happens the very first time after you install the application.

Steps to reproduce:
1. Start with a fresh system.  Unsure if an uninstall/reinstall is sufficient, if not, install GIMP on another machine that does not yet have it.
2. Run Gimp.  (If it matters, open a .jpg file and then from the menu bar select Filters > Distorts > Polar Coords; unsure if this step affects anything.)  From the menu bar, select File > Save As.  Note that the Save Image dialog box is too small and has the help button on top of some of the other controls.
3. 


Actual results:
The first time you do this, you see the messed-up window described above.  The second time you do this, it works fine.

Expected results:
I expect it to work the first time as well.

Does this happen every time?
No, only the very first time.  It works normally on subsequent attempts.

Other information:
To verify, I installed GIMP on a new machine and once again saw the same bug only once the very first time on the second machine as well.