Advice on beginner’s dulcimer
Instruments- discuss specific features, luthiers, instrument problems & questions
Certainly looks good for a starter instrument.
As mentioned, the tuners are easily tightened to keep the tuning pegs from slipping. Tighten them 1/8 turn, and then try to adjust the tuning and see if they still slip.
New strings -- you'll want "loop end" strings, not "ball end" strings. Any set of strings labelled "Dulcimer" will be adequate to learn with. DO NOT take off all the strings at the same time. Take off one; replace it. Then take off another one...
You may have broken that middle string because you might have been trying to tune to "the wrong A". Do you have an electronic tuner? If not, here's a link to audio files where you can hear the correct notes to tune to:
http://susantrump.com/tune-your-dulcimer.html
When tuning strings, Do Not tune 'still' strings. Hold the tuner and pluck the string. While it's still humming, give the tuner knob a quarter turn. If the sound if the string did not go up or down, STOP, and move the tuning knob back. You have the wrong tuner for that string. Try again.
FYI, I've attached a copy of an article I wrote several years ago called I Just Got A Dulcimer, Now What? It is an illustrated glossary of dulcimer terms so we all speak the same lingo. Plus it has answers to many beginner questions about the tuning, playing, care and feeding of your instrument.