I just test with success SPMPT 2.0 on MAMP 1.9.
Upgrade to MAMP 1.9
If you have to upgrade, you need to keep the repositories and tracs folders, and configuration files (/Applications/MAMP/conf/apache/my-repository-for-example.conf) and then, include them in the new /Applications/MAMP/conf/apache/httpd.conf.If you need help, contact me as usual.
Regards
Cédric
