Slow when administrator opens form first

[kenlo]

A database is a FE and BE shared with a workgroup of several people. When
one form which contains subforms is opened by the Administrator first, other
people who have lower level access can open the same form. If this form is
opened by a lower security level person first, the administrator cannot open
the form, the hour glass will stay forever. Other forms have the same
problem, however, the administrator can open the form after a long while.
Can you please advise what and where the issues should be looke at?

Thanks