Expression/Mechanism of ROR1 in healthy tissue
Examining the literature it'd seem that the ROR pathways incl. ROR1 and ROR2 are critical for developing tissues in the majority of cases. We also see relevance in the expression of ROR1/2, more specifically ROR2, in cases where taxic cell types are required to migrate, branch, etc. Most of the literature determines much of this occurs through a noncanonical Wnt signaling pathway.

Wnt5a–Ror–Dishevelled signaling constitutes a core developmental pathway that controls tissue morphogenesis

Ror2 Receptor Mediates Wnt11 Ligand Signaling and Affects Convergence and Extension Movements in Zebrafish

Ror2 regulates branching, differentiation, and actin-cytoskeletal dynamics within the mammary epithelium

Notwithstanding the abnormalities we see in neonates with knocked down ROR, is it wrong to assume we'd see developmental defects of branching tissues in developing (or juvenile) organisms such as lung, mammary, neural, glandular tissue, etc.? Some data in that respect would be interesting, but it's also illuminating given the presence of ROR in cancer metastasis and EMT events.