Hi @Tim Edwards , i loaded the layout , but there seems to be below warning msg , due to which my nmos got blank ain console display active (Tcl8.6.10 / Tk8.6.10) Processing timestamp mismatches:File sky130_layouts/sky130_fd_pr__nfet_g5v0d10v5_2R6UFX.mag couldn't be read sky130_fd_pr__nfet_g5v0d10v5_2R6UFX. Loading DRC CIF style. Also getting message during saving : "Failed to read entire subtree of cell" When do we have these kind of messages ? Thanks

It sounds like perhaps you did not do a "save" after creating the parameterized cells, and so those cells got lost from the design. The GDS has instances of those cells, but the cell definition does not exist in the GDS.