CONFUSION REGARDING TAXI INSTRUCTIONS AS CTLR WORKLOAD HVY.

Narrative

WX WAS LOW IFR. ATIS INDICATED ILS APCHS TO RWY 4R; DEPS ON RWY 9. APCH WAS AT MINIMUMS AND ROUTINE. CLRED RWY ON TXWY (HIGH SPD). NEW FO INITIALLY GAVE THE IMPROPER POS; WHICH I IMMEDIATELY CORRECTED. LCL CTLR WAS WORKING LNDG RWY PLUS DEPS ON RWY 4L; RWY 9; AND RWY 15R. DEPS ON RWY 4L AND RWY 15R NOT ON ATIS; PLUS XING LNDG ACFT ON RWY 4L AND RWY 15R. HIGH SPD 'Y' (WHERE WE CLRED) HAD GREEN IN- GND TAXI LIGHTS XING RWY 4L (THIS IS ALSO RWY 33R. THE LIGHTS WERE ON ON THIS RWY ALSO). CTLR ASKED US SEVERAL TIMES ABOUT OUR POS. HE DID NOT SEEM TO KNOW WHERE WE WERE. HE WAS EXTREMELY BUSY. HE THEN TOLD US TO CONTINUE ACROSS RWY 4L; THEN ASKED US AGAIN OUR POS AND TOLD US TO HOLD SHORT. I TOLD HIM WE WERE PAST THE HOLD LINE (BUT NOT ON RWY). HE THEN TOLD US TO CONTINUE AND HOLD SHORT OF RWY 15R. CONCLUSION: THE WX WAS LOW. THE CTLR COULD NOT SEE ACFT ON GND. CTLRS ATTN WAS DIVIDED BTWN LNDGS; TKOF ON 3 RWYS; AND ACFT XING RWYS. THIS WAS A VERY CONFUSED SIT AND EVEN THOUGH WE KNEW OUR LOCATION THE CTLR'S INABILITY TO PLACE US ON THE ARPT BEGAN TO CONFUSE US.