Make sure WINCEREL=1 is set in your sources (or sources.cmn) file so the file is copied to the FLATRELEASEDIR automatically. If the component you cloned is linked to a catalog item that is already in your workspace there is nothing you have to do (apart from building your cloned DLL and do a makeimg). Your cloned DLL will overwrite the original DLL in your FLATRELEASEDIR and all should be fine. If the DLL you cloned is not linked to a component already in your workspace you can either add the component to your workspace or copy the registry entries for the component from its registry file (like common.reg or some local registry file used by the original component) to platform.reg and add an entry for the DLL in platform.bib, then do a sysgen in your BSP folder, followed by a buildrel (to sysgen and copy the modified platform.reg and platform.bib to the FLATRELEASEDIR) and finish with a makeimg to create a kernel containing your cloned DLL (and its registry settings).
RE: To include the dll in the final image
Make sure WINCEREL=1 is set in your sources (or sources.cmn) file so the file is copied to the FLATRELEASEDIR automatically. If the component you cloned is linked to a catalog item that is already in your workspace there is nothing you have to do (apart from building your cloned DLL and do a makeimg). Your cloned DLL will overwrite the original DLL in your FLATRELEASEDIR and all should be fine. If the DLL you cloned is not linked to a component already in your workspace you can either add the component to your workspace or copy the registry entries for the component from its registry file (like common.reg or some local registry file used by the original component) to platform.reg and add an entry for the DLL in platform.bib, then do a sysgen in your BSP folder, followed by a buildrel (to sysgen and copy the modified platform.reg and platform.bib to the FLATRELEASEDIR) and finish with a makeimg to create a kernel containing your cloned DLL (and its registry settings).