I’ve read your post, but i serisously does not understand why you would use an id inside shortcode.
This is a very bad way of thinking the developpement.
This amazing plugin (not mine, i’m just an user like you), let you insert in a page, with a really simple shortcode, all the Collabpress system.
So, why whould you have an id ? If you do this, you will need to create a new page for each new project .. There will be no more automatic process .. If you do this, you break the main functionnalities of this plugin.
Maybe that you have a really good reason, that make you want to use id inside shortcode, but i’m pretty sure that there is a very better solution, in copying templates files to your theme folder, and then edit them. You can recreate or rewrite all the functions beeing called from there .. THIS IS how you have to modifiy the plugin.
Else, you can also create a “sub-plugin”, which will ‘extends’ the collabpress plugin (work only if the plugin is written with classes (don’t remember this is the case here :p)
If you’re not familiar with plugin or shortcode creation, i strongly recommened to change the way.
Maybe that you should consider explaining why you want to use IDs in shortcodes, instead of modifying templates files.
Cheers.