I've been using track saw systems for many years. I had Eurekazone system for probably 15 years and just this past year switched over to a cordless Makita system. I got rid of my EZ cutting bench and replaced it with a MPC. Liked it so much I bought a second.
Today to break down sheet goods I use a newer product from Eurekazone called pyramid (believe they are available on Amazon). You can thread an included 3/4" peg in the bottom that fits perfectly into the MPC and the top has slots to accept 1x lumber. So I for a full ply sheet I make four assemblies which include: a length of 1x4 and two pyramids. Put these on my MPC's and life is EZ rip cutting the ply.
For crosscuts this pyramid solution is a little cumbersome since the ply pieces are smaller and it's more difficult to support them. I'm thinking some kind of cutting board would work best for this. Something like the MFT where you make a kerf cut into the top but I wouldn't need dog holes in it.
Was thinking I could:
1) just temporarily put 3/4" ply or MDF on the MPC tops
2) could make the table bridge with 2x4's and lay a cutting board on it
Wondering if someone has already done this so I don't re-invent the wheel.
I have always used a piece of foam board insulation. It's light and will last quite a long time if you're somewhat careful on the depth of your cuts.
You should be able to find it Home Depot or any other similar store.
I've used foam board quite often but it's hard to use a saw track with clampsthat attach underneath.