No, it doesn't work that way. Just do as Pali suggested - at best, it will fix Your problem, at worst, it will filter out possible source of issues. U-Boot is just different kind of low-level, when reading required bits - it may work well via filemanager, SCP or whatever, but be too FCKD up for U-Boot. Which seems to be the case - You said already, that for U-Boot directories/filenames are FCKD.

/Estel