Hey there! Thanks for your interest in LightBit.

Yes, when you're mining using all the cores of your CPU, they're already busy solving a complex mathematical problem which makes it almost impossible to use the computer.
I believe you can choose how many cores you want to be mining from and how many you want to keep idle to continue using your pc. This will affect your hash rate tho, but at least you can use it side by side where your pc makes you money.

Please feel free to join us on discord where you can find miners and a guide on how to do such. Thanks!