Hello everyone.
I'd like to add something to this post. I've been experiencing the same issue.
I usually used the auto cruise set to x8 speed on 200LR/F. After the SP1 and 300ER extension (which is the only thing that changed on my configuration), it is not possible anymore. I've installed the planes following Ryan's guidelines for the clean install (sweeped everything PMDG T7 related).
So basically, the issue is the following for me:
On autopilot, auto cruise enabled to x8, the plane starts banking and keeps trying to get back on track. On such situation, the auto cruise should get back to x1, which it doesn't. Also, when disabling the auto cruise (through FMC or short button on the clock), the simulation gets back to forced x4 mode, that needs to be manually set back to x1 through FMC or tabs menu.
I use:
PMDG NGX
PMDG 200/300 SP1
Pro ATC X
Shade
FSUIPC
Active Sky next
I hope these details related to the auto-cruise engine will help you guys. Thanks again PMDG for your creation, really bringing some passion into this world .
Youssef D.