1) Is it possible to delete a Resource once it has been uploaded?
If you want to remove a Resource that you already shared with a Participant, but don't want to permanently delete the resource, you can learn how to do that here: http://help.coachmetrix.com/knowledge_base/topics/remove-a-resource-or-collection-from-a-participant
2) How do Resources and Collections work with multiple coaches on a project?
The Account Owner is able to share Resources and Collections with any Participants or Projects in their Account.
The Account Owner is not able to share Resources and Collections directly with another Coach on their Project. But, the Coach will be able to see Resources and Collections shared with Participants to whom they've been assigned.
A Coach can share Resources and Collections only with Participants to whom they've been assigned.