hi big, thanks for the input.
As I remarked in Help forum (I also post there), problem is fixed.
Yes, first of all I was looking for any option in View menu related to grid. Also I checked Grid button was on instead Slip or another grid option.
After all these checks, I decided to reinstall the prog, using the Repair Option, which reinstall everything, taking care of your settings, but, problem still was there.
So I started to check every little checkbox in all Options/Setup menus and submenus. Then I found "Show grid in edit mode" disabled.
What I am concerned is about I never disabled that parameter since I worked last time (yesterday). I am considering that maybe I pressed a keyboard combination (like CNTRL + any other key) which disabled that,.
The right thing is now I can see the grid
E-mu EMAX. Yamaha DX7, DX7 II FD, DX27S, Roland JP8000, D10, JX-8P. Korg POLY800. Casio CZ1000, Casiotone MT-70, SK1 (lost in my house), Commodore C64 w/ prophet64. Akai S3000 XL HD. KURZWEIL PC1x