help with 2 amps and a few delay pedals

ok so im gonna try to get this right. here is my set up. TELE>TU2>BLUES DRIVER>BIG MUFF>BOSS CHORUS. the boss chorus has stereo out puts so from there half my signal goes into a 65 supro valco amp, then the other half goes into two DD6 delays, TEC 21 DLA, and a LINE 6 DL4 delay then into my 65 DRRI. hew.

so the problem is that when i engage the chorus pedal (which has a direct line going to one amp, supro, then another signal traveling through the delays into the DRRI) the sound from the DRRI drops about 80% and sounds nasally. out of phase?

but when i do not engage the chorus effect both sound full and nice.

It also seems that my settings on my delay pedals are not producing the same results as before. and being as how all i have added is the supro's dry signal before the delay pedals i am not sure how this is possible. the delays sound jumbled though their settings have not changed.

anyone using a second amp with multiple pedals that have had this problem?

should i move the supro's signal further down the chain?

I dont truly understand the concept of an effects loop. i see on my solid state Ultimate chorus amp there is an effects loop input on the back of the amp. there is no such thing on either my supro or my Drri.
A. is it still possible to create an effects loop with out a staition dedicated to it on a amp like my ultimate chorus.
B. if so is this what i need to fix the problems stated above.

know there is a lot of little questions here so any help understanding would be appreciated. Thanx, Jeb

You'll probably get more replies at the Stomp Box section of the forum.