Perspective Scripting to find a Custom Property on a View

I think system.tag.write has been depreciated (and it's "system", not "System"). You should be using system.tag.writeAsync or system.tag.writeBlocking. Note they expect the tags in list format - even when only one tag is sought (but I think it will tolerate one tag without the [ ].

Can you right-click on custom.UDT, copy and paste it in here so we can check the contents?

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