Fixed in r9252, soon available for testing at https://builds.openmpt.org/builds/index.html

It would be great if you could confirm whether this and the other reported issues have been fixed in the testing version.

Tested in 1.28.00.04. Spinner does not get stuck when following test steps.

It does seems as though the valid range for the restart position is based on the highest value used, so the following is possible:

• Create a sequence of patterns 0 1 2
• Set restart point to 2
• Remove patterns 1 and 2 from the sequence
• Change restart point to 0
• Click up on the spinner, and you can still select position 1 or 2

Clicking up on the spinner should probably do nothing if it would result in a value that's higher than the position of the last current pattern.

It's even easier than that - you could just manually input a high enough number (provided that the order list grew big enough previously). I have no intention to "fix" that though, since technically there is nothing that's really broken.