The connection serialisation is causing the craft load to fail:
1. download craft here
2. see it's not massively broken but piston doesn't move on slider 1
3. drag away square base, then re-attach where it was to reset connections
4. try to load
5. craft fails to load
I found the offending line was
<Connection partA="11" partB="1" attachPointsA="0,3" attachPointsB="0,1" symmetryId="f4fbacbe-efa9-4a79-8a2e-4523163bf584" />
changing that to attachPointsA="0" attachPointsB="0" fixes it but breaks the piston. This is how I uploaded it.
@mjdfx150529 must report all the hugs ;)