Hey Jay,
How I really feel about SFQ? Ah, I can take it or leave it!

But seriously, folks...
One thing that can help with losing weight is to bend the knees slightly more when you practice active exercise. This opens up the so-called "belt channels" and can help expedite the losing of weight.
The schedule you outline sounds fine. Just keep at it; consistency is key also.
As soon, as possible, try and do whatever exercise you can do with your eyes closed (if you are not already) even with the DVD. Try and transition to the audio coaching on disc 5 rather than the DVD as soon and as much as possible. Even if you can only do this with the first two or three exercises. This can help focus the energy internally and help with visualization. After all, if you first use the DVD and then you are only using the sound, to some extent or another, you are now visualizing the movements. That alone can develop this facility.
I know the problem with visualization, and I have a similar problem. I think using water at this level would be fine. If possible, try to see if you can transition it to light and use a color--any color that comes to mind easily. Lately, I have been using green a lot, because Green Lantern has always been my favorite superhero (supposedly a movie is in the works) and the color green comes to me easier than others. But on Level II, there is a lot more need for color, so I am playing a lot with cycling through different colors.
One thing that Chunyin Lin suggests in Level II that can work in Level I, is have colored lights or something of a color handy right before you close your eyes and then visualize that color. That can help. It is worth a few minutes of your practice time to conjure up some color(s). The brighter and more vivid the better. This helps move energy.
And for those people who are not so visual, sound can also work. I sometimes use either the sound of "om" or even "shalom" or just humming sounds or whatever. You can use musical tones or the sounds of music that you play in the background (such as the "Inner Beauty" or "Back to the Universe" "soundtracks" that Chunyi Lin includes in the course) and try to imagine the sound penetrating your body and filling the space and the channels.
Chunyi Lin says something that is helpful to me and I have read it quoted here a few times: I paraphrase here:
visualize. If you can not visualize, imagine that you can. If you, can't do that, pretend that you can. If you can't do that, lie! In other words, the act of using your mind to move the energy will work and eventually, your mind will forget that you are "lying" and you will be better at the visualization or mind intention.
But basically, any image that comes to mind easily can work. I had a teacher who suggested using the image of more solid matter, but I like things that have more flow much better.
If you need to use water, for example, when visualizing the transparent column running from the head to the bottom of the torso, then by all means go for it. Just see if you can play with the color of the water a bit.
And that is also another key for me at least: play. Have the spirit of play as much as possible when you practice. That can help with motivation as well as progress.
Basically, use what works for now, and if possible, try to set a goal to make the images more transparent and flowing even than water.
That is a great question and perhaps others will have different responses. That is my two cents for what it worth (with inflation, probably less than .01 cents, but hey, .01 cents is .01 cents, right?

)