Hello Aaron,
The only reason you might not be able to open CVI 6.0 UIRs in 5.5 is if you have 'Lab Style Controls' on your 6.0 UIR. In CVI 6.0 the Lab Style Controls were introduced, which are not available in previous versions of CVI. If you want to be able to open this .uir file in an older version of CVI, you must convert all the Lab Style Controls to Classic Style Controls. The option Convert UI to Lab Style under the Tools control bar will not convert Lab Style Controls to Classic Style. In order to convert Lab Style Controls to Classic Style Controls, each Lab Style control has to be manually replaced with its Classic Style counterpart. Once you have done this for all of your controls, you should be able to open the .uir file in CVI 5.0 or 5.5.
I hope this helps Aaron.
Wendy L
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