Could be the same cause as AWBPR-70.
Compiling attached two archetypes gives a segmentation error.
The error is occurring because nested differential paths are not supported, and they are not cleanly processed even in terms of errors, which I'll have to fix. But the attachment openEHR-EHR-OBSERVATION.protocol_diff_overlay.v1.0.0.adls is probably what you were trying to achieve with the second anyway. This shows why nested paths are not normally needed. Nevertheless, I'll investigate whether it makes sense adding support for them.