The TACT will work with multi-directional speakers, but that doesn't insure that you will like the results. The TACT system works by measuring the frequency response at the listening position, but it's not as simple as you might imagine. At low frequencies it uses a long time window for the measurement and thereby captures the direct and reflected sounds. As frequencies move higher the TACT shortens the measurement window to effectively only capture the direct sounds and ignores the contribution of room reflections. Their research indicates that this type of complex measurement system best mimics how the ear/brain hears sound. The effect of the TACT may or may not be to your liking because the direct sound from your speakers will have improved frequency response, but the reflected sound may not. It's possible that the reflect signals could be made less smooth by the applied room correction. If your speakers are well setup such that the reflected frequency response closely mimics the direct response, then you won't have this problem.
I use the TACT 2.0 with Martin-Logan electrostats and I'm very happy with the results. It's a very powerful and effective device, but it does have a steep learning curve.