Hi.
How I can gain clan's founder rights due to inactivity for a long time of current owner?

I told about that clan: http://www.gametracker.com/clan/mxplrs
I'm one of admins of current project's servers (can be found in my favorites).

There are no other members we could potentially transfer ownership to.

In your case, transferring ownership is not a possibility.

You can create a new page here:

http://www.gametracker.com/teams/