New contact of engaged unitl

This is a photo of a query that arose during a game a couple of nights ago.
The photo is a picture after combat has been fought so need to back track a bit.
The avtive command is the one at the bottom of the picture consisting of 3 LU's (the one on right lost re rank in melee).
At the start of the turn the active player 1st moved LU unit on left and carried out side attack which was drawn. Then moved middle LU to be in a position to give flank support when right hand unit attacks. Then attacked with right LU and in doing so recontacts the unit that is engaged to its side.
The query is which units fight/reactivated. Have re read 7.7.5 and 7.7.8 but still not sure.
We ruled the side melee was not reactivated and the re engaged defending unit didn't count as support against frontal attack as pre occupied elsewhere. The ref's quoted seem to restrict to where there is an enemy front to there own front.
Think we should have included re engaged unit as a support against attack to its front. Is this how you see it?

Unless I am missing something this situation seems pretty straightforward. 

Melees are determined by main units. Support units cannot be main units and main units cannot be support units. So far so good.  

You have two distinct melees going on with two main units on each side. The fact that the right side LU is  contacting both enemy units is irrelevant. Each enemy unit is engaged with a different main unit. The attack of the right LU at the end of the sequence of attacks does not reactivate the other melee. 

That means you did it correctly.

Yep, that seems correct.

Weird position for the left-LU and mid-LU to have got themselves into though.

Thanks as i thought. Put on forum as one of our group suggested that the example at bottom of page 47 says 'reactivates the melee' could be construed as both melees.
Zippee i know the side attack looks a bit strange and in fact both of the other 2 players on that side advised against it and should move straight ahead thus fight with the middle LU.
In his defence although all out of position but fairly safe as on end of flank under no threat. Think he was trying to avoid losing rear unit of middle LU as had 3 losses. As it happens at end of turn command just 1 away from breaking.