FWIW, I think these two items from Andrew may be related somehow
I think the suggestion to 'run as admin' was an attempt to understand/solve the problem, not a statement that RealBand requires this
and
There has occasionally been situations where the program is unable to delete RebuildStylePicker.txt for some reason, usually related to wonky permissions
(run as Admin changes permissions)
Though the suggestions from users here may seem strange sometimes, I believe they are offered with a sincere intent to help.
Testing narrows things down.
This is how things get solved.
I deal with this stuff every day, so it stuck out to me.