Hi,
The demo doesn't have such limitation. Is difficult to know what is causing this without looking into the scene. It could be a bug or user error. Please send us the scene if you can.
First, I would check if you are generating the hair on a polygon selection instead of the actuall mesh where you want the hair to grow. In Guides from Surface and Hair from Guides look for "Use Sub-Selection".
Check if this happens only with hairs or if it also happens with guides.
Disable every modifier after Guides from Surface and check the guide count.
Disable every modifier after Hair from Guides and check the root/hair count.
Check if you have any texture maps or strand channel set as distribution multiplier in Guides from Surface or Hair from Guides.
Jeordanis Figuereo (Product Designer. EPHERE Inc.)