Dirk,
Any chance that you have the Related Location on the form and set Use Alternate Label Text so that it appears to be the Building Location instead of the Look Up Field.
Here is a screen shot of that situation
In my case above it will say Parent Name to the user but will show the record ID like in your case.
If that is the issue, you fix it by using a Proxy field that shows the information form the related table as opposed to the record ID, Here is a screen shot from a Parent Child Relationship
On the form I use the field Parent-Name which allows the user to select any Parent record instead of using the Related Parent and the unfriendly Record ID#.
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Don Larson
Paasporter
Westlake OH
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