I have a lot of unused reversing track can this be used as regultrack by cutting wires or just using it

I have 2 4x8 tables I have put them in a L shape  so my layout area is 8x12. Having trouble deciding on a layout. Would like a track around the  paraimeter with some trains inside and maybe a over under with tunnels. I am using HO silver EZtrak and some of the turns are tough?  IDEAS? also can Bach Ho flex track be combined with ez trak? This would make some corners easier?  HELP

Can terminal joiners be used with ez track? If not is soldering still the best way to get current to track ? Also I have heard of new type glue which  connducts electric

I I can't seem to keep cars coupled. Every turn (22) one or 2 come uncoupled. KNUCKLE COUPLERS  Kincade Xmas Train  HO    HELP!