You specifications are almost clear. Now the opinion is: You need to explore user-exit IWO10009 using FM STATUS_CHANGE_EXTERN.
- First of all, this might not work during Order Creation.
- During IW32, when First Operation status is set, the above FM should be used to change the Equipment user status.
- For capturing the operation change status you may have to take clues from this post Restrict Operation changes after Order Release
Requirement being complex, this is a job for a skilled ABAPer. May wait for other experts opinions.
Best of luck
KJogeswaraRao