About the Call Recorder Widget:
After successful tests of call recording, I contacted the developer of the app I liked most for this type of task. I asked for loosing of the market compatibility restrictions of the app. Unfortunately, the reply I received was not addressing the market filtering issue at all. Never the less, to my surprise, the app appeared available on Market for Milestone some days later. I was able to buy the app directly on Milestone on 8.2.2012. Later, the app became filtered out for Milestone again. It's not appearing in the Milestone's market search as of now.
My guess is that the dev of the app does not want your money...
About the beeps during call recording - they are not generated by the call recording app, it's a feature of the proprietary Motorola's libaudio that allows the call recording...