Liz Story: ''Solid Colors,'' (Windham Hill C-1023.) This is another in the fine collection of disks rolling off the presses at Windham Hill of late. Like many of the artists in this stable, Liz Story is young (25), highly talented, and plays music that is drawn from jazz-classical roots. Not surprisingly, a few of the selections on this album, especially ''Water Caves,'' are strikingly similar to the piano of fellow label-mate George Winston. For a first album, this is a strong offering. Story's piano is sensitive and shows a capacity to mix styles and pace. The best of the album is its frame: the first and last songs of both sides. ''Wedding Rain'' opens the album with a shower of notes through an enchanting melody. The close of side one, ''Things With Wings'' is a runaway dash across the keys that enthralls and leaves us gasping by its finish. Story is often a pianist at play, and this is obvious in the bouncy, upbeat title track, ''Solid Colors,'' which opens the flip side. To finish, she plays a stirring, almost haunting rendition of ''Piece Peace,'' composed by her colleague Bill Evans. In between these four highlights, the music seems to lack focus, but on the whole this is an impressive debut.