Waiting to get the full version (ordered it yesterday), so I've been fighting the demo mission....it sounds the same as the "tutorial" mish you guys are on about.....
After a very harsh introduction to the LOS available to the defenders, I've managed to make some progress.
If you nudge your artillery spotter and mortar crew to edge of the crest (without actually "cresting" it) and then use a very small move or sneak to get them into spotting position, they don't attract fire. The AI does seem to employ counter-battery artillery though if you keep your spotters in the same place for a few rounds.
On the attack, the Axis has a shortfall of armour quality. The 50mm gun of the PzIII's is overmatched by the 75mm guns of the allied tanks and if you try and slug it out at 500 metres, you are going to get slaughtered. I've chosen to wait for all 3 panzer squads to appear on-map, get them assembled out of LOS on the left of the map and use fast moves to try and keep their initial exposure to enemy fire at long range short.
There is another hill crest halfway towards the allied positions, which I usually have 2 panzer squads move to and then start engaging for real. I'd suggest getting some infantry as close to the left flag objective (but as out-of-sight as possible) so they can be used to advance and engage enemy AT teams and infantry whilst your PZIIIs hunt the armour. The 3rd panzer squad can get into a good firing position near the left edge of the map on a ridge about 250m short of the left flag objective - hopefully you will get some side armour shots from one or other of your panzer teams.
Expect to take some knock-outs, just keep a focus on applying the "Schwerpunkt" tactic.