I'm finally making some progress but would appreciate some help.
a) getting on ladders to go up is easy. I can't figure out how to get on them to go down! Mostly I have given up and simply jump - ouch! What shoud I do?
b) do I need to keep trinkets such as the bauble stick and locket? I created a character at the Inn and let him hold the odds and ends in case I need them later.
c) should I keep special items like the Mavin Signet, the shaman's spear, etc with me forever? Or store them with my character at the Inn and return when/if I need them?
d) I am fnially at a point where I can start developing special abilities such as identify and repair. It says the characters are in training. What does that mean, and how do I practice / enhance the ability?

Hope these aren't too obvious. Many thanks.

I can't answer the climb down ladder question. Many have tried and failed. I just jump.

You could store certain items at the Inn. But if you do, you may find it very inconvenient to go back and get them. For instance, if you dump the bauble stick with a character in the Inn, you may wish you had in one of the dungeons. You will have to work your way out of the dungeon and back to the town to get it, and then work your way back into the dungeon again.

Also the Mavin Signet is an item you will wish you had with you more than once. It's probably not going to inconvenience you too much if you drop of some weapons you are considering keeping, etc.

Do any of your characters have the spear skill? The shaman spear (from the Toad Village, right?) was a great weapon to use for quite a while.

Finally, your character will be in training until they advance another level. Then they can use their newly acquired skill. I changed character classes several times for my characters. Thus, it did not take so long for them to advance another level, and they acquired many skills. (They don't acquire skill points to spread around as fast when you change classes though -- At least not until their new class equals the same as the highest level of their other classes.)

Hope this helps.