For what it's worth, the bowl is designed to hold a certain amount of water. If any more water than that flows into the bowl, it may initially appear to raise the level a bit, but the level will settle back to the bowl's design. 40% refill ratio combined with a fill of the tank to the right height on the gmax flush should fill or slightly-overfill the bowl. (One of the ways they reduce to 1.28 from 1.6 is to try to eliminate overfilling. Because each flush doesn't empty the bowl exactly the same way, there was a tendency on old toilets to just overfill in order to make sure there was enough water. Hence on many old toilets, the bowl will refill and then more water will keep running into it for 15-20 seconds on most flushes, but on others it will only overfill for 5 seconds. Even on the Gmax there is occasionally a little overfilling on some flushes, but not on most.)
The tank water should never be running down the overflow riser (of course, the toilet will send water down that riser from the refill hose). That's because if a properly-functioning valve doesn't shut off by the time the water level gets to the top of the overflow riser (hint: "overflow"), the water in the tank isn't likely to rise much higher, and then there will be nothing to signal the valve to shut off. The issue in your toilet is that I can plainly see the water exceed the height on the fill valve that would normally cause it to close (shut off), but the valve delays shutting off. Why? Dunno. In any event, that extra water isn't going to give you a higher level of water in the bowl after the toilet has settled for a minute or so; it's just going to go down the drain.
It might be worth taking that valve out and washing it off, besides just cleaning the filter. It may do no good whatsoever (it does do good with the Korky valve, but maybe not this one), but it can't hurt. Right now, you seem to have a valve that's just a smidge away from not closing at all, which would give you a runaway toilet that hopefully won't overflow into the room, depending upon how well the overflow riser can capture the water running into the toilet from a valve that won't close. If it were I, just because I like fooling with this stuff, I would replace it.
In Canada, Korky products are distributed by Lyncar (800-263-7011). According to them, in Edmonton, you can get the 528MP at any of the following: AMRE Supply (2 locations: Downtown and South), B.A. Robinson (Robinson Lighting & Bath Center), Bartle & Gibson, Best Plumbing & Lighting Design Center (a Toto dealer, too, but get the Korky valve b/c it's cheaper and a better design than the one you have), and any one of the branches of Emco Alberta. I would call over before going to make sure (1) they have it in stock and (2) they will sell it retail, as some of these guys may be wholesalers.
Good luck!