Ok I had my first game with Tau last night and a few points have cropped up from that little adventure, the first is Drones, I had a Baal Predator shoot a flamer at my XV8 body guard and commander which succeeded in knocking wounds off everyone and killing all my drones because its not really clear as to;

A, Do shield drones get the 4+ invulnerable save from their Shield generator, (i said they did, but conceded the point because I couldn't really prove it),

B, And this goes for other drones as well, but im more interested in shield drones, does it matter where the drone is placed in comparison to what is being shot at to gain the benefit from it, an Example, My XV88 got shot at from behind with an assault cannon, as luck would have it my opponent rolled 2 6's to wound me and killed me outright, he said I didn't get the benefit from my shield drone because, it forms a unit as such and you aim/ take casualties from the closest unit so my XV88 didn't get the invulnerable save and died without really doing anything because he shot me from behind and my XV88 WAS the closet target, I thought this was a bit odd as essentially it is a bit of war-gear,

Secondly, Marker lights. It says that Marker-lights can be used to increase the BS of any unit shooting at that target INCLUDING overwatch, however, in the Marker-light entry it says that Marker-light counters stay next to the unit(im assuming target here) until the next PHASE, im assuming they mean shooting, assault etc, are they referring to the friendly unit or the target unit, basically I want to know, if I shoot a Marker-light at a target, is it painted onto them for the duration of my whole turn or does it expire at the end of, like it says each phase, if thats the case how is that supposed to benefit my unit shooting at a MARKED target when it assaults me if the bloody thing gets taken off!?

I appreciate Im probably making that sound MUCH more complicated than it actually is, but with the way it is worded, in the heat of a game, especially when it is a bit of a crunch moment, it is a harder argument to make when it doesn't appear to be written that well in the rulebook/Codex, anyone who can make sense of my Gibberish and explain it to me gets +REP

Thanks

all drones while taken as upgrades are actual unit upgrades and make new squad members. Shield drones do get their invul but they dont give it to the squad. time to start placing them better to block shots. So in short shield drones should have got invul save against flamer and xv88 should have died. Always use drones to shield

Plus he wouldn't get a kp unless he killed the drones as well.

As fallan said, SDs have a shield gen giving them (and them alone) an invuln.

Q1) They are members of the unit and the way you place casualties in shooting is nearest to the source of the shot, who takes each hit until dead then keep going. This means if your suit was nearer than the drone the shots are allocated to the suit not the drone.
This means you have to be very careful about placement of your suits and drones, and are very vulnerable to being flanked.

Q2) Markers dissappear at the end of each phase. To benefit from markers in overwatch you have to use them in role of supporting fire (Tau Special rule), overwatching with markerlights then getting another unit to shoot their overwatch into the charging unit

Gents thank you that clears it up niclyrep to follow

It should also be noted that if the suit in the back was your HQ (or a character) they should have gotten a Look Out Sir roll to try as well.

Even with a drone?

If a wound from the pool is allocated to a character, the character gets a "look out, Sir!" roll. The wound then can be delegated to the next nearest figure. Some tau units get to automatically pass "look out, Sir!" rolls, Suit Bodyguards and Stealth Suits with Shadowsun are the ones that come to mind.

once attached to a squad , the drone is part of that squad , its also infantry in its unit description .
Soyes you get a look out sir with drones

Nice. I never thought of a drone acting that way, sounds odd even saying that. Sweet