Hi jbrandim,
The first parameter in the find() function is a string, so when you use this function with VBS syntax, you need to enclose it in double quotes:
FirstValue = find("Ch(56) > 5.0", 1)
Additionally, you can also call this function as a Formula Calculator function, since it is in fact a DIAdem function and not a VBS function:
Call FormulaCalc("L1:= find(Ch(56) > 5.0, 1)")
FirstValue = L1
The cryptic error message is an artifact of the translation process between VBScript and the DIAdem find function. DIAdem automatically maps the return value of the find function, which is an integer, to the variant variable "FirstValue", as well as the input parameters. The mapping process from Variant to string in the first find() parameter failed, and
that led to the error message you received.