I have a video of our software which put into a device. It does not allow me to make the background transparent so it looks a little unprofessional. Right now you can only change the color of the background but I would love to be able to make it fully transparent.
Are you referring to the ability to produce the final video so that when it plays on a device its background is transparent? (if so, I'm not sure I've ever seen that happen, but thought I'd ask)
If you are referring instead to a video you placed on your Timeline where you want part of it transparent, Camtasia does offer a nifty feature named "Remove a color" where you choose the color you want to become transparent and adjust from there. Seems to work quite nicely.