I had a value in the %FieldUserOptions that was a pipe delimted value.
ValueTips(Unpaid Invoice|Paid Invoice|Cancelled Invoice)
executed this in my template. This command should return then contents of ValueTips between the ().
However, it returns an empty string.
Changing %FieldUserOptions to this value corrects the problem.
ValueTips(Unpaid Invoice,Paid Invoice,Cancelled Invoice)
This is definitely related to the | pipe character. User semi-colons also works.
ValueTips(Unpaid Invoice;Paid Invoice;Cancelled Invoice)