PLEASE HELP. Growatt SPH6000 Hybrid Inverter, It wont... Hybrid.

Hey guys. I've been stuck for days on my first installation. I installed a Growatt Hybrid SPH6000TL BL-US inverter with a Transformer/Automatic Transfer Switch to power an EPS panel. 

The person that sold it to me (and Growatts website), told me that this inverter could use solar power to power loads and supplement with grid power when needed. Then if the grid went out, the inverter would automatically transfer to powering -just a separate EPS panel, effectively Islanding the unit...

So long story short I finally have everything installed per the manual specifications. I currently have (7) 390w 48v panels running in series. With (4) 12v Marine batteries running in series to get to the required 48v. When I turn the unit on in "off-grid mode" it runs beautifully. The battery keeps the inverter powered on, The Solar panels work charging the batteries and powering the load on the EPS panel. SO, here's the issue. When the inverter and transformer breakers are turned back on, to connect it to the grid and main service panel, it just stays in standby mode. It rechecks itself over and over and never comes out of standby mode. It doesn't utilize any of the solar or battery power that it IS showing is available. No faults. The green light is on on the unit saying everything is normal. I assume that, given the way it is and isn't working, that its just a settings issue. 

Growatt in California seem to be "busy". They said they would have a technician look at the inverter settings (online) and try to set it the way I want, which is to work on grid but Net-zero meter (NOT sell back to the grid). But it's been a week and they haven't returned any more calls. My distributor said they would help if growatt wouldn't help but they seem to be busy too and haven't offered much support either. 

I've played with the settings as much as I can and still can't figure out why it's not playing well with the grid. I've changed the Voltage setting to 240v and 60hz to match US standards. When I try setting it to "Grid First" mode just to see what it does, the setting fails to apply. I THINK I've managed to set the batteries to charge and not discharge when its reached 100% SOC (to save power for the evening). I don't know if it's WORKING that way but that's another lesser issue. 

If anyone can offer any suggestions I'd be eternally grateful. I can't find a useful operation manual anywhere that explains all the settings. Just the installation manual that doesn't cover half of the configuration settings.

Thanks!
Mike