So far, I haven't noticed anything other than the warnings.
If I have some UI usability issues who would I tell about those? There are some frustrating things about trying to use GGTS on a netbook with a small screen. The way screen real estate works, sometimes I have to resize my window beyond the size of the netbook screen when trying to get access to some elements. I have run into this problem when trying to use the 'Install new software' feature. The list of items to install is invisible unless I unmaximize the screen ad stretch it out some. The same problem exists for details that are displayed if you select one of the items in the list.
The best thing to do is to raise an issue on our issue tracker:
https://issuetracker.springsource.com/browse/STS
Please attach screenshots and your screen resolution
It may be that the problem has more to do Eclipse and is not related to GGTS in particular. But, raise the issue and we will have a deeper look.