I've merged Project Q with a very old HAK system on a PW. It was not CEP, but I learned how to work with Q. So I will explain the basics to you once, and then let you give it your best shot with CEP.
There is also Project Q's forums. Others have tried this as well and shared their experience. You should read what they have to say.
However if you are not going to use Q's creature overrides, while you will still benefit from Q, you should ask yourself why you are bothering to do all of this work. The creature overrides are a significant part of Q's value.
Anyway...on the road to merging the HAK systems, the main incompatibility has to do with Shields and Weapons. The easiest solution is to choose Q's resources or CEP's resources, and override the other.
If you want to use Q's version of these items do the following:
(1) Q WEAPONS: Include q_!armoury at the top of the hak list.
- Q's weapons have the same number of weapon parts as CEP, however they reserve the top part for VFX, and put the existing bioware models of the weapons in the lower two weapon parts. You will still have access to other CEP weapon resources, but the two systems can be confusing side by side.
(2) Q SHIELDS: Put Q's 2da hak above CEPs hak baseitems 2da
- Q's shields have 3 parts. CEP's have one part. The two systems don't work together. To use Q's shields you need to use their baseitems 2da. To use CEP's shields you need to use their baseitems 2da. The key difference between these two 2das are the lines for shields. Q's has a setting for multipart items, CEPs does not.
- If you want to use both of Q's shields and CEP's shields you need to use Q's system and make CEPs shields work in that system. I don't recommend doing this since it is a great deal of work, and Q will be adding new shields to their hak soon - but its your choice.
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(1) CEP WEAPONS: do not use q_!armoury hak
(2) CEP SHIELDS: put CEP's baseitems 2da higher in the hak order than Q's.
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Regarding Q creature overrides:
The easy way to avoid using some of Q's creature overrides is to not use any of Q's creature overrides. Simply do not add Q's creatures hak to your hak list. If you want to customize which creature art is used from Q, then you'll need to create your own creature override hak using Q resources. This is not recommended. If you are going this route you might as well just combine select creature haks from the vault.