How exactly do you want to swap the design table? (are there conditions built in?)
If you're doing it manually, wouldn't it be a bit simpler to create a parameter, and assign it to the configuration relaion in the design table?
In other words, create a parameter, make it integer, call it "ConfigNumber". Now, go to the "Relations" portion of the tree, drill down to your design table, expand the relations under it, until you find "Configuration." (Configuration=X) Create a formula on this parameter, and insert the new "ConfigNuber" parameter in the formula. Now, when you want to update it, no more opening the design table - just double click the parameter in the tree, change the number, hit enter, and wait for an update. Also, this should make it easier for you to automate, if you have the intention of doing so. (although I can't understand why, just based on your question)
I don't know if that's exactly what you're after, but I do hope that it helps.
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