R:TW - Strange flaming shots issue

[Buster]

Hello everyone

My initial problem was that when i toggled flaming shots, the fire animation was not visible on arrows. Before releasing and upon hitting target, you could see the light of the fire, units were burned, and there are effects of smoke and explosion.
I reinstalled the game, and verified it via Steam. Drivers are up to date. I checked the related .txt and .CAS files too.
So i started checking the settings, AA low, high, off, smokes, glints off, effects detail medium off etc, but nothing.

Background:
Because i have optimus enambled notebook(win 10 i3 hd4600+840m) like many people, i am cursed with the campaign map lag and stutter, slow pointer movement. So i found a solution on steam forums couple of months ago, you had to download and copy a d3d8.dll file into the main folder, and it fixed everything, it runs like butter. No lags, no frame stutter nothing.

However, out of curiosity, i copied d3d9.dll from system32 windows folder, and replaced d3d8.dll and voala i had proper flaming arrows, but the lag came back on the campaign map. (probably it is using the integrated vga).

Why is this happening and is there a way i could make this work? Yes, i can live without flaming arrows, but it would be nice to sort it out.
Any suggestion?

[Ruprecht]

I don't see why it would be reverting to your on board gpu while using dx9. I think it's more likely that your HD4600 can't handle the game in dx9. Not to sound rude but the 4600 is a pitifully slow gpu. I would expect a lot of lag with it.

The ultimate solution being a more powerful gpu so you can run in dx9 and have your flaming effects. Not much else comes to mind sorry.

[Buster]

Thanks for the input!

I do have a capable gpu on board which is the nvidia 840m. The problem is while it does not using it hence the lag.
It's a common problem with optimus enabled laptops. I tried to force it in nvidia control panel but no use.