Secure Wroshyr Garden
There's no great mystery to the first segment of the Wroshyr Garden; just keep moving forward, putting your soldiers into the positions that become available, and make sure none of the Trandos can get behind you. There are three Trando HAMs in the area, so save your sniper rounds and flashbangs for them. There aren't any bacta dispensers here, so you'll have to be mindful of your teammates health and revive them when they happen to get incapacitated.

Find Generator Console Alpha
After blasting through the door, heal your guys up, place one in the sniper position near the next door, then blast through and clean out the room beyond. You'll find two anti-armor positions here, so get people in both of them before moving into the next room, where you'll find a Trando HAM. Like all good-hearted Trandoshans, he'll be more than happy to follow you back to the anti-armor room, where you'll be able to get your teammates to take him down while you chip in with sniper fire.

After the Trando's down, grab his ACP Repeater, then move through the room beyond and heal your teammates up again. Another locked door stands between you and Console Alpha, so slice it open, then rush your soldiers into the sniper and anti-armor positions here to take down yet another HAM. Add his ACP Repeater ammo to your own, then heal your guys up at the bacta dispensers in the last corridor before attempting to slice the generator console.

Slice Generator Console Alpha

Your ACP Repeater will come in handy against the incoming Geonosian Elites.

Now, as the multitude of sniper positions might intimate here, you're going to have a little fight on your hands while you attempt to slice the console. Set up two soldiers in the spots on either side of the walkway here, then send in your other soldier to slice, but be careful; you're going to have a solid minute of fighting against Geonosian Elites here. It's a Herculean task, especially on hard mode. The only tips we really have to offer is that the ACP Repeater Gun works well on the Elites when they happen to stand still for a minute, and that the large electrical orbs in the upper reaches of the generator will instantly kill an Elite when you shoot them while one is flying by. Beyond that, surviving the fight is a matter of reviving your fallen soldiers and hoping that the Elites don't happen to target your slicer; if he can complete his slice, then all of the Elites in the generator will be instantly killed.

Slice Generator Console Beta
Console Beta is in a similar room to Alpha, save for the fact that there's only a single sniper position at the outset; if you want another one, you'll need to destroy the fuel tanks near the console itself. We found that keeping one soldier on the snipe point near the door with another one near the console gave us pretty good coverage on the Elites as they flew up, but don't forget that you can task all three soldiers to the snipe spots while you slice the console yourself, if you wish.

Moving Upstream

Locate Separatist Cruiser
You're going to find yourself in the middle of a difficult fight at the beginning of this level, as both droidekas and SBD's will have overrun the next room over from where you start. If you can establish a beachhead with AA shells or EC grenades, though, you should be able to work your way through the room, and get your troops into positions that ring the door leading on. When all of the enemies that are going to come through have done so (the last spawns are a pair of droidekas), run around the room until you find a recharge of EC grenades, then form up and move through the door to take on an SBD dispenser. With a soldier tasked to laying charges, you can focus on taking down the SBD's themselves with the grenades.

Secure Hangar
There are a couple more SBD's in the next hallway. Instead of avoiding them by breaching the door to the left, take them on; after killing them, a Wookiee will appear in the far doorway, who'll lead you around to another locked door. Slice this one, and you'll gain access to three sniper positions which you can use to snipe away at the oncoming droid forces, who were going to try and ambush you. The positions will be able to kill them quite handily, so just stay back and make sure that you're not in your teammate's line of fire.

Taking on these guards from long range is the best course of action.

When you reach the nearby hangar, you'll soon be ambushed by a trio of Grievous guards. Luckily for you, there are a pair of Wookiees here who will take most of the hate, assuming you positioned yourself properly. You'll notice a turret flanked by a pair of fuel tanks near your end of the room; if you shoot these out, then you'll have a pair of sniper spots and the turret in which to position your team, which should allow them to kill off the guards from long range. If they start closing in on the Wookiee nearest your position, then throw EC grenades at the lot to stun them all and wear their health down further. Before moving on, check the hangar for more ammo.