>I am creating a new app which needs to use the business objects and the database of another app.
>
>I'm running into some initial problems, and I was hoping for some feedback.

I've done something like this both ways. I have one app. that will eventually have a totally different look and feel from the main application, but uses all the same code functionality of the main app. In this case, I just used the same project and added code that would shut-down the menu, toolbars, forms, etc., then bring up the new UI (eg. it's a desktop app. that can also be run in a "kiosk" mode and used via a touchscreen). This actually worked out OK.

I've got another app. that isn't really a full instance of the MM's framework (eg. I didn't create it with the QuickStart wizard). It does make a few calls to business objects in another project. This was also easy enough to do.

The basic reasoning I used to choose between the two methods was: Is there a possibility this app. will require extensive hooks to my existing app. in order to make it work. Also, is there a possibility that I will need to include a significant number of new class libraries, functionality, etc. in one app that the other app. won't need. If I answered yes to either or both, I would create a new project for it. If not, I reused the existing project. When reusing the existing project, I also added a command line parameter that can be passed to the application on startup that would tell the app. to select the alternate behavior. No parameter: standard behavior. Parameter: New behavior.

In your case, it's probably a toss up between the two. I might be inclined to go with the single project, though. That way you could always easily run this "server mode" on any of the workstations, and you've only got to worry about compiling and distributing one app.

HTH