I don’t appear to have those fonts on my PC but I do see a problem with the bounding box for Gill Sans MT on RH5. Gill Sans MT Condensed is behaving fine.
Development on RH5 has stopped and I tested this on the WIP for RH6 where the internals for text are totally rewritten.
The same font appears to be working fine here:
You can download the WIP from the Serengeti category here on Discourse.
@lowell, RH5 presents me with more / different fonts than RH6, is that as expected?