When deploying in a sandbox environment, are you restricted to the actual deployment size of your project? I Know that you have 100mb of data and 100mb of file storage space. When you deploy the application, does the disk space of the created application take up the 100mb of storage space or is the disk space of my application irrelevant when deploying in the sandbox environment?
The 100/100MB limit is for database size and deployment size. Database speaks for itself; deployment size is the size of your application (mendix model, theme, resources) plus your uploaded files (System.FileDocument).
You can check the size of your deployed app by unzipping the MDA.