Hello,
take the current Debian version and also the current i-mscp and it should all run without problems. Update your current server to i-mscp 1.5.3. I have already moved some servers according to the instructions you mentioned without any problems.
This is the correct answer for the initial question. Always check the i-MSCP repo and readme file which versions are supported so you know what distro you can use!
For any other questions, please open a new topic, for any bug reports please use the bugtracker