It seems that buttons created in FMP 12 behave properly but those that come via conversion do not.
This bug was reported to FMI during the pre-Release software period. But feel free to remind FMI that this bug is still an issue... Please.
It happens when changing text attibutes, including color, on converted buttons. It seems that converted buttons are treated as text blocks rather than the same as fm12-native buttons, but even the alignment of the text within the button is ignored in the resizing.
If I build/replace the old buttons with the FM12 button tool, the new buttons are OK, but it doen't seem to matter how many times I have updated, set states for, and readjusted any pre-12 buttons -- they continue to behave badly if I touch the text formating again later.
I'll add my voice to reporting this bug, which is a very serious matter in terms of productivity. When a solution contains many hundreds of buttons, the dimensions of which are critical to the UI and the operation of the layout, then changes caused by this bug are a matter of great concern.