David, it is not recommended to use Master projects in
Project Server. As you have experienced, it will not
accept a multiple resource assignment on master/slave
projects as well as if all the subprojects were already
published and you publish the master, your resource
allocations will double in your enterprise resource pool.
Two possibilities exist for what you are trying to do:
1) Publish subprojects only and keep the master project
local to your machine and insert subprojects each time
you open all the files to your machine. You will need a
fairly powerful machine to do all of this if these are
large projects.
2)Use milestone links in and out of the projects. i.e.
Summary Task in the Master project might be something
like Configure Servers. Two subtasks under this could be
Infrastructure Start Server COnfiguration and
Infrastructure Server COnfiguration Complete. These same
two tasks would be the very first and very last subtasks
in the Infrastructure sub project but listed as maybe
Receive Servers for Configuration, Server Configuration
Complete. The tasks would then be linked between
projects.
Hope this helps.
Kevin