The runtime edition is just a stripped-down distribution of the WebUI Test Studio Dev/QA Editions. So if you have the Ultimate you can also use it for running tests. Just install the Dev Edition you have on each machine you want to run tests. Note, you won't be able to use one and the same license on two different machines at the same time but you also don't need to activate the Dev Edition on the machine you'll use to run tests only.
As to the library and the source code, no you won't be able to run tests using the library only. The registration is complicated and requires registry updates, VS updates, etc., operations we don't support manually.
I hope this helps.
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