Wow what a greatt community here. Thank you everyone for your great suggestions.
I think my issue is the upside down lander can which was the first part I placed...so i'll remove it, let the command pod take root control and give that a whirl.
I've tried many aerodynamic setups using various wings/fins etc with no luck, so I'm sure it's not as aerodynamic issue, but still thanks for the tips.
To add more detail on my lander concept, the pilot controls from the command pod (which imtsssue clearly messed up on by having an upside down lander can as my root lol), transfers into the lander can, undock and fly that plus the science lander to the mun, land, do stuff, then detach leaving the science hardware and landing engine behind, dock the lander can with the command pod which still has an engine attached, transfer back to pod, dump lander can, fly back to kerbin etc.
I may have gone a bit ott with the comms, solar etc but it looks the part I like an air of realism in games like this so I expect my comms sats for example will have more antennae and power than needed...but if it looks the part, I feel better. Obviously some compromises will happen in due course as i learn more about kerbin rocketry.
I'll post a screenshot of something that works if it turns out to be the upside down lander can causing the problems. ..or a screenshot of a failed design if that doesn't fix it.
Thanks again for responding quickly and with several things to try. it will keep me busy tonight
Fly Safe