Well, this is what the log, entirely says:
(remember I use the exe you sent in a 2.5 instalation... probably it won't work as you wanted, tell me if I must install version 3 and try this again)
06/06/2016 21:40:33 - Unable to scan folder 'C:\Users\Miguel\Music\'
09/06/2016 13:35:30 - 10.0.10586.0 - 3.0.6001.37050 - System.TypeInitializationException: Se produjo una excepción en el inicializador de tipo de '#=qfyzAQnce$5rChxXPMzNRxr$RkGePI0cCNw9mWRSP6Pw='. ---> System.IO.FileNotFoundException: No se pudo encontrar el archivo 'C:\Users\Miguel\Downloads\MusicBee\Configuration.xml'.
en System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
en System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
en System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options)
en #=qfyzAQnce$5rChxXPMzNRxr$RkGePI0cCNw9mWRSP6Pw=..cctor()
--- Fin del seguimiento de la pila de la excepción interna ---
en #=qfyzAQnce$5rChxXPMzNRxr$RkGePI0cCNw9mWRSP6Pw=.#=qQU_k8QhAjj2skMY5OVq3LQ==()
en #=quFak$JVNnbqvdvC8TxPBHqbHaOg93sVK$GJ4wsXKkFg=.#=qfbuwS1Yf1R0WH_pq$LQQVw==(#=qM2OA_T$PTF0zuM5_yoXZcgxKDR7lIgzYaazGdT0CMxk= #=qxazrOTZVn8GxFbwqTs3HdA==)
en MusicBee.MusicBeeApplication.#=qwEy4QqghD8vciZC2VXw6TA==(String[] #=qwXbhYSLEivoyoxmKl0ggJg==)
09/06/2016 13:36:26 - 10.0.10586.0 - 3.0.6001.37050 - System.ArgumentException: Ya se agregó un elemento con la misma clave.
en System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
en System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
en System.Collections.Generic.Dictionary`2.Add(TKey key, TValue value)
en #=quFak$JVNnbqvdvC8TxPBHqbHaOg93sVK$GJ4wsXKkFg=.#=q$xFJkaYJ$qFBeJ0HG$Q2QQ==.#=qSGOi6kj28wOJ1scnCVlX$Q==(List`1 #=qGt7kCc5xnv3mpst$N33P6g==, Boolean #=q$kdyJoqtXL9WD4YT8FVfyjTynZCRdk6TWvnlFDlJZeE=, Boolean #=qxdyyaUGM4j9ljPmiGWU5OQ==, Boolean #=q_ZtY7xg2ikHLG4$P_Q_a9A==, String[] #=qSWgrx7HCgwxOybST2myiieBSq2NcYjRW_JWfJcvlinw=, Boolean #=qeBW99reL18JU1TMduGIxsmNC0_G91k1BLdYbBA5_DSQ=, Dictionary`2& #=q_fqVAlLiaPZPvz1v_8H4Ug==)
09/06/2016 13:36:26 - Unable to scan folder 'C:\Users\Miguel\Music\'