You can convert Tajima embroidery format (.dst) for the one used in Compucon/Singer machines (.xxx) using any of the available embroidery design or conversion software. Both these formats appear to be fairly well supported, so it should not be that of a problem to find a tool capable of dst to xxx conversion.
Open DST file Open XXX fileAn embroidery designs manager
A converter for embroidery designes
A popular embroidery design and printing software
Advanced version of the popular Embroidermodder
A home embroidery software
An embroidery design tool from Janome
A free embroidery editor and converter
An embroidery editor and converter
An easy embroidery and apparel decoration design software