Capital Investment Grant Program Improvement Act of 2020 This bill revises and extends through FY2025 the fixed guideway capital investment grant program. Specifically, the bill (1) increases funding for the program; (2) revises how the Department of Transportation (DOT) evaluates and rates new fixed guideway capital projects under the program based upon, among other things, a consideration of inoperability; and (3) directs DOT to report on financing and technical barriers to the construction and operation of fixed guideway transportation projects with a total estimated capital cost of not more than $500,000 in small urbanized and rural areas.