I must admit I have no experience with that particular program (or any other version of "Construct"), and I'm unsure of whether a similar-sounding problem in Construct 2 could be related at all, but this seems like it might (hopefully) be relevant:
Flicker between sprites - Scirra ForumsSolution from the linked thread: "It could be that they are placed between pixels. Go to the view ribbon and set snap to 1x1 grid. Then select all of your objects, move them away a little and back again with the mouse."