Have you tried starting with template Finance&Budgettnig from new.mendix.com. Probably covers a big part of your requirements.
As to why your image is not appearing, that probably has to do with access rights. Go to your domain, double click the ExpenseReceitptsUpload, click tab Access and add an access-rights rule for the module-role (probably User) the gets allowed to see the image.
Don’t forget to add that modulerole ‘User’ to a Projectrole (See ‘Project’ → ‘Security’) that is granted to the you have signed in with.