Hello Matthew Kehoe,
Which version of Keil uVision are you running? I tried with the newest version 5.26.2 and I didn't face any kind of problems.
Be sure that you have the corresponding packets installed.

Select the debug interface that you want to use depending on the firmware that you have on the OpenSDA of your FRDM, in my case is J-Link.

Once you select the corresponding interface click on the setting button and you should see something like the following.

Please let me know the results on your side!
Hope it helps!
Victor.
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