Hi Zhen,
[quote user="Zhen Li"]Connect MDL seems changed a lot of.[/quote]
Yes, a lot. Even a simple 32bit > 64bit brings a lot of changes, other changes are result of a transition from C-style API (former MDL) to C++ API (MicroStationAPI). Plus structural changes (split into separate layes like DGnPlatfrom, MStnPlatform...).
[quote user="Zhen Li"]IS there any instructions to convert old MDLs to the CONNET version? [/quote]
This was discussed during BDN workshops. There is a conversion tool delivered with MicroStation SDK installation. It doesn't solve everything, but at least can help to automate renaming of MDL function to a new form.
With regards,
Jan