I've replaced the AND gate located in your program with one found in Multisim (7409N), and the program works fine.
It seems the issue stems from the AND gate you are currently using. Could you please post the "and.ms14 " file so that we can have a look.
Just to be sure, have you also attempted the troublshooting steps outlined here:
The and gate created with nmos and pmos in attach.
I played already with the settings, but also the voltage being used has impact.
It works with vntol=1e-4, abstol 1e-10, itl1 500, itl4 500
I wanted to use 2.5 or 3V but it looks like I need other nmos and pmos components to make it work.
That's quite curious, the simulation worked instantly and correctly for me. I am using:
vntol = 1e-012
itl1 = 100
itl4 = 100
Could you try these same values, and make sure that your Multisim is completely up to date on upgrades?
Hope this helps