With the Canning Machine in "Fluid Enrich Mode", if you have water in the left tank, put a CF Sprayer in the Top Left slot (not apparent from the arrows), and CF Powder in the middle slot, the machine will make foam and put it into the sprayer. If the sprayer isn't in the machine, but the water and powder are, it seems to make foam into the right tank, but loading it from there into the sprayer is the issue, as you have found. I believe if you put the sprayer in the top left, and at least 1 bucket of water in the left tank and one dust in the center, that it will load the foam from the right tank while it is making the new foam. I did this once or twice today by accident, but I haven't gone back and retested and checked amounts, etc. I'm running build 209 at the moment.
And for those, like me, who had trouble figuring out how to get water into the left tank- make a universal fluid cell, fill with water by right-clicking water in the world (like you do with a bucket), and then right click the canning machine with the filled cell. Note that this doesn't work with a bucket, although you can put a bucket INTO the machine, but I could only make the machine unload the bucket into the right-hand tank, and couldn't use that for CF foam.