Hi @pankajoutworx and @mantispta ,
Just wanted to let you know that we detected the issue and are working on fixing it.
The issue happens when installing Mantis on a non-standard MySQL port (different than 3306). In the meantime, if you can free your 3306 port, you should have no problems installing.
We expect to release a new revision of the stack tomorrow or on Friday, but we'll let you know once it is released.