I'll try to help you based on the info you posted
It looks like you may have let go of the switch when opening the top, which is what resulted in the OP Suspended message.
If, after that message popped up, you tried hitting the trunk release, then I believe that's correct that there would be no response, because the car hadn't been reset to either a completely open or closed state, and since the trunk moves as part of the assembly, it locks it out so to not cause any damage.
This would also be why you had a red alert icon......the top was in partial open mode.
I'll leave out the checking of the trunk lock, as that didn't make a difference either way in the situation.
So, the car let you close the top, which again would be expected, since it was in a partial open state.
AND....that is correct it will keep telling you to stop the vehicle because you have to be at an almost standstill in order to operate the top.
Again, I'm just writing this based on the order of things that you stated, but it looks like you either released the button while the top was opening, or (because you mentioned that it told you to stop the vehicle) you were going too fast when opening the top and the top shut itself down (....but, I tried that once and if memory serves it actually gives a different message than OP suspended).
Hope that helps.