I used a similar model US Stove product - the CAC. It is just about the same as your Ashley, looks the same but has a slightly bigger firebox. I used the CAC for several years burning mostly anthracite coal. I also initialy had difficulty in starting coal fires, but have found with a little experience, it is easy. Here is what I do.
Start a reasonaby sized wood fire with the stove about 1/3 to 1/2 full maximum of wood. Turn the thermostat to about 1/2. At this setting, the wood will burn to produce a good, thick bed of red coals. After an hour or two, check the fire, and when it is mostly a thick and healthy bed of red coals, level it out with a small rake (I use an old golf club). Quickly place about 20 pounds of coal evenly on the coals and then close the loading door, but leave the ash door open. When this coal has started to ignite, fill the stove with coal to the top of the firebricks. Close the loading door and leave the ash door open. Watch the stove carefully and when the coal has started to have flames come through it and blue flames appear when you open the loading door, the coal is lit. Close both doors and enjoy up to about 24-hours of coal burn time.
One thing I found that really did not work was to burn coal and wood together. The coal burns only some and the wood smolders and produces creosote. Another problen with beginners is that they don't put in a good load of coal. A shallow bed of coal burns poorly and for only a short time before extinguishing. A thick bed burns satisfactorily and almost to completion and can be regulated very well. A good be of coal on a mediul draft setting burns more then 24-hours in my stove. Be prepared to take out a full pan of ashes avery day - coal makes tremendously more ashes than wood.
Also, when you are recharging a coal fire that is low, shake it with the shaker grates and also rake through it with a suitable tool to shake all the ashes out. If the fire is low, throw a few small pieces of wood on it and let them burn until they have produced good red coals before reloading with coal. If you don't do this, coal fires can be tempermental and can go out.