I have some 1970's era Bachmann HO rolling stock that I'd like to upgrade with modern EZ Mate couplers.  The trucks and couplers are mounted with some sort of "rivet".  There's no screw to dis-assemble.  I could probably force them apart, but I dont wat to damage them so the cars are useless.  Any info on the best way to convert these would be appreciated.

Do all current Bachmann locos and rolling stock come equipped with the EZ Mate magnetic couplers?

I currently have two separate DC EZ Track ovals running two separate locos.  One of the ovals has a left and right turnout to make a small oval within a larger oval.  I recently purchased EZ Command plus and both left and right DCC ready turnouts to convert that to DCC.  Now that ive done that im thinking about connecting the current DC oval to the DCC oval using more DCC ready turnouts.  Ive read that on DC layouts you can short circuit the system with too many turnouts.  Is that aconcern with DCC layouts as well?  Is there a general rule of thumb about how many turnouts or crossovers you can have on a DCC layout?

Why doesnt Bachmann offer accessories for curvred ez track like curved bridges, railroad crossing gates for curved track or roads that butt up to curved track.......etc.  Not all layouts are big enough to afford to run all of these things to or over straight track.  Thanks.