[flatbutt]

I burned wood for 25 years before going to a pellet stove.

Coal requires air to come from beneath the fire bed to burn more efficiently. You can burn coal in a wood stove but not very efficiently.The shaker grate helps you remove the ash from the hot coals again for greater efficiency. You'll find coal ash to be more of a pain than wood ash as it flies around much easier.

The paint in the shaker can is just fine but you need to "cure " it with a small fire and it will smoke like the devil when it is curing so keep the windows open.

Check all of the "rope" seals around the door for breaks. Does the stove have a secondary chamber or a catalytic converter? If so check the condition of the insert making sure it is not clogged.

Invest in chimney cleaning kit and use it! Burning well seasoned hardwood is best. Softer woods will coat the chimney with creosote increasing the chance of a chimney fire. But hardwoods are not perfectly clean either.