How to analyze a piano leitmotif representing memory amid nonlinear textures?

[Ella.J]

I'm a film student working on a thesis about the use of leitmotif in modern cinema, and I'm currently analyzing how a particular composer uses a recurring, fragmented piano theme to represent a character's fractured memory across a non-linear narrative. I'm trying to go beyond just identifying the motif and understand its harmonic and orchestral transformations. For others interested in film score analysis, what are your methods for deconstructing a composer's thematic development, especially when the score is densely layered with electronic and acoustic elements? How do you approach discussing the emotional and narrative impact of the music without relying on subjective impressions alone? Are there any specific software tools or analytical frameworks you find indispensable for this kind of work?