Are you wondering why some functions are not possible because the button you want to use is greyed out?
If the button you want to use in AssetAccountant is unable to be clicked, is greyed out or just doesn't seem to appear at all in the interface, it may be because your User permission access is at a lower level than you need to perform the desired action.
Here is how User Roles are arranged in AA: User Roles
Only more senior roles can allocate an access level for you of "Account Member" and/or "Register User" or higher.
If you need higher privileges, contact your manager or the AA account Owner and ask them to increase your access level.
See also: Granular User Role permissions and privileges to determine what level of access to AA you require.