Problem with Hurricane (bug?)

[Kos023]

I have been playing quite a lot of BugWave lately, I really enjoy the game and I have found that using a combo of a Ring of Fire and a Hurricane separated by one or two great walls can be extremely efficient, especially when juggling the bugs. However, there seems to be a bug with the hurricane tower where the animation on top of the tower stops me from clicking on it (or any tower near it for that matter) and upgrading it. The only solution I have found is to juggle the bugs away from the tower, so I can upgrade it, but at higher levels with the greater range, it is difficult to do at times.

There has to be a way to make it so that the animation on top does not stop th player from selecting the tower. As it is right now, I'll put down and upgrade all the towers I want to have around the hurricane, and then put down the hurricane and upgrade it, while trying not to give it time to shoot at creeps until it is completely upgraded. It works, but requires a lot of timing and plenty of cash on hand to do it. If at some point in the process the hurricane activates, I end up being unable to select any tower under the hurricane animation and have steer the bugs away. On a level 3-4 hurricane, that's not exactly easy.

Is it supposed to be like this? Or is it a bug?