Hi,
Your mileage may vary on Mono, but I can tell you what I do when I test on Mono.
1. Replace the contents of Web.config with the contents from Web.net35.config
2. Set this to false in Web.config <add key="EnableOpenIDAuthentication" value="true"/>
3. from the command window cd into mojoPortal.Features.UI folder and do sudo chmod +x mdpostbuild.sh
4. Rebuild the mojoportal.mono.sln solution in MonoDevelop
Note that the solution is pre-configured to use SQLite. If you want to use pgsql, you need to edit references on mojoPortal.Business, drop the project reference to mojoPortal.Data.SQlite and add a project reference for mojoPortal.Data.pgsql. Same thing with mojoPortal.Features.Business, you drop the reference for mojoPortal.Features.Data.Sqlite and add the reference for mojoPortal.Features.Data.pgsql
Hope it helps,
Joe