Were you making futomakis (ie, sushi rolls)? Sounds like you were.
1) The two major types of nori that I am aware of are the sheets that are not
spiced and the ajitsuke ("flavor added") nori that are spiced. The later is
usually shredded as if from a paper shredder or in bunches of small sheets (3-4
cm x 10 cm). Use the large unspiced sheets. (I use ajitsuke for
onigiris--unseasoned or salted rice balls like you see in samurai movies or in
box lunches) When I was a child, my mother used to quickly pass the sheets over
a flame (I don't know why; maybe so it won't get soggy as fast?) because she
didn't do it later and didn't teach me to do that.
2) Overly sticky, gummy rice is usually from too much water. In my family, my
rice tends to be drier (I use less water) than that from other members of the
family--my grandfather liked it gummy, almost like okai (very soggy, recooked
rice often given to the sick). The usual trick is to flatten your hand on top
of the uncooked rice and fill water until it covers your hand. I use regular
short-grained rice rather than special sushi rice to make sushi but assume the
same applies when measuring the water.

When I make sushi, I take the hot rice and put it in a large, flat-bottomed
wooden bowl and spread it out. I'm lazy and use the powdered sushi seasoning.
Either with the powder or DYI seasoning (ie, water, vinegar, & sugar -- be
conservative and add the later slowly so the rice doesn't become gummy), mix it
in and stir around the rice to cool it off. I stir it around several times
until it cools (1 hour or so). I am usually preparing some of the ingredients
for the rolls while the rice is cooling.
To keep the rice from sticking on your hands (or if you use sushi forms), mix
up sushi seasoning (water, vinegar, sugar) and liberally wet your hands with it
each time you handle the rice. Less rice sticks to you, and therefore, less
mess -- of course, I like to eat the rice that sticks to my hands.
I hope that this helps. I'm not a sushi chef and the above is what my mother
taught me for family gatherings like New Year's. A pro may give you better
instruction.
STEVEN