Quotas
As you can see on your home page (on top of My QA Systems title), there are quotas for the number of QA Systems based on graph and text. Both of these quotas' default value is 5. It can be changed by an administrator.
Shared QA Systems are not counted in the quotas.
If you have reached your quota, you will not be able to create new QA Systems. You can delete existing QA Systems (of the corresponding type: graph/text) to create new ones.
You can also see these quotas on your profile page.
There are other quotas for the size of the files you import. The default value is 5MB. It can also be changed by an administrator.
For text-based QA Systems, since we can add several files, we want the collection size to be less than the quota. For example, if the quota is 5MB, we can add 5 files of 1MB each, or 1 file of 5MB.
When you create your QA System, you can see the size of each files and chose accordingly which files you want to add/remove.