Additional Study Information: The purpose of this study is to assess the safety and tolerability of an experimental study drug called ulixertinib (BVD-523) in the treatment of advanced cancer that shows certain genetic alterations (changes in the DNA) called MEK or atypical BRAF alterations and is getting worse. Experimental means that ulixertinib has not received authorization to be marketed for use within the USA. Ulixertinib works by inhibiting (blocking) tumor cells ' EKR1/2 pathways, which can cause the tumor to stop growing or spreading. Cancers include bladder cancer, colon and rectal cancer, head and neck, kidney cancer, liver cancer, lung cancer, pancreatic cancer, and prostate cancer.