Few questions about Stepmania

Hello ! I'm new here, and I strated playing 5 or 6 months ago. I have a few questions which I wish someone will answer c:
First, when I was playing at start, Stepmania had no problems saving my preferences, but now, since I did several profiles, stepmania only saved my speed at 700M, and if I change it in 725M and quit stepmania, shen I re-open stepmania my speed is still at 700. And it's the same with all the others parameters I had, and I don't know why. If someone has an explanation, i'd be glad to listen.
Second, I noticed that some song's name are in yellow, and other in red. Has anyone a clue why ?
Stepmania
Thanks ! And have a good day c:

The SM5 default theme, like every StepMania default theme since 3.0 before it, colors songs with charts on any difficulty besides Expert that are 10s or harder (in dance mode, anyway) red.

As for why it doesn't save your speed mod, I'm not totally sure about that. If it also isn't saving scores, it's probably not saving your profile.