I tried doing that once & the pasta was awful! Soggy, pasty, all lumped together...I can't think how to describe it. I had heard of people doing it though & asked for advice here. The way that worked best for me was to add the pasta (without any additional liquid!) about 20 min before serving. I did it with noodles, though, & stirred it well throughout the stuff in the crock.
I found Tips for Adapting Recipes for the Crock Pot at:
Southern US Cuisine
If a recipe calls for cooked pasta to be added, cook it until just slightly tender before adding to the pot. Add 1/4 extra liquid per 1/4 cup uncooked rice, and use long grain converted rice for the best results. For long-cooking recipes, add cooked rice shortly before serving.
I've never done crock pot lasagna, but here's a favorite "plain" recipe of ours:
Five Flavors Chicken
3 - 4 lb chicken, boneless
2 cloves garlic
1/2 c honey
1 1/2 tsp ginger, ground
1/2 c soy sauce
3 Tbl sherry
1/2 c crushed pineapple with juice (opt)
2 Tbl cornstarch
Mix garlic, honey, ginger, soy & sherry. (Can substitute orange or cranberry juice.) Dip chicken into mixture. Place chicken in crock. Mix pineapple with sauce & pour over chicken. Cook on low for 6 hours. Remove chicken. Blend cornstarch into juice; cook to thicken.
(Don't use chicken with bones as the bones kind of distintegrate.)
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