File Manager doesn't work?

I’m sorry to point out that I have mount other QNX drive to change /usr to /user directory of this drive.My system is QNX 6.2.1PE. As you comment, /usr is a system directory and can’t be moved or deleted. Now I’m in other troubles. For my operation steps is as follows:
1:copy /use to /user. I have to spend too long on this step ,so I kill cp process.
2:boot from other QNX drive and rename this drive’s /usr to /user.
3:boot from this drive and find /usr appear again. I’m so glad to use pfm again! But, I made such a terrible mistake: I delete /user directory!
4:Now I’m in great trouble of using qde. It can’t find qconfig.mk, qtargets.mk!
I’ve copied qtargets.mk to this drive and made a link of qconfig.mk as follows:
ln -s /usr/include/mk/qcon-nto.mk /usr/include/qconfig.mk
Yet qde keep telling the same error.
My God! Should I only have to reinstall QNX again?

I would reinstall, god knowd all the stuff that need to be restored, links an all.

Even you QNX master have decided to reinstall, what else can I do?
Had known that divastaging effect, never would I make so much effort to recover this foolish error!