This is an interesting concept and the difficulty is balanced. Anyway, I see many improvements to this game.
First, the graphics. They're too basic and I don't like it at all, especially the blobs and the color merger. You could also improve animations, such as the bounce. It's rather confusing.
Then comes the gameplay. Keyboard shortuts are OK but it could be handful to have also the arrow keys to change directions.
At first I didn't see the purpose of the three colored buttons. I thought I had something to do like coloring conveyers or something. Some description could help.
Also, how many color blobs does it require to beat the level? I have no idea. I guess each collector have a counter. You should display that counter, either in the form of digits, or a progress bar or whatever. Also a step counter.
Finally I'd like to say that I often felt in need of more room. But I suppose it's part of the difficulty. Is it? For example, I can't hope to find the beginning of a solution to the "Congregation" level.
The level editor is a great plus! I look forward for additional levels. Or maybe a sequel. Anyway, keep on working!