The verilog netlist contains more than 40 thousands component. When I import the netlist into cadence, it gives me an error of "Illegal bus reference - Can't tap "Neta" from "Netb".". I looked through the generated schematic, it messed up Neta and Netb. I cheked the Schematic Generation Options befoe importing the netlist again. The Maximum number of Rows/columns are limited to 1024. Is it possible to increase the Maximum Number of Rows/Columns of the schmatic before importing the large netlist?
I suggest you contact customer support. You didn't say which version you're using - which is quite important as there have been a number of fixes related to Verilogin.
You could always turn off the Full Place & Route option, so that it doesn't attempt to fully route the schematic. You could also decrease the density - it's a slider on the form. But without knowing what the real issue, it's hard to be sure. 1024x1024 should be OK for 40k components.