This is why i love open source ! Thanks all.
Via Serial (eg to minmosd) Multiwii only outputs a total of current used,though before it calculates that it actually has the current consumption rate as read by your hardware sensor. (in my case rctimer current voltage sensor).
MinimOSD can show both total current used as "mAh" and current consumption rate "A" (amps) , though as multiwii only outputs mah and not amps to get minimosd to show Amps you would have to connect the sensor to minimosd instead via a hardware mod involving soldering to arduino's legs... (and then enable minimosd ADC)
So here is how to get multiwii to pass amperage reading to minimosd and get minimosd to display it

im using stock mwc 2.2 release on mega 2560, and KV_Team_OSD_dev_r345 release on hobbyking mimiosd board
So starting in mwc sketch, open "Multiwii" tab in Arduino editor:
Make Line 296 Look like this:
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static uint16_t intPowerMeterSum, intPowerTrigger1, amperage;//haydent added amperage
Around Line 562 make it look like this:
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//lcdprint_int16(pMeterRaw); LCDcrlf();
powerValue = ( conf.psensornull > pMeterRaw ? conf.psensornull - pMeterRaw : pMeterRaw - conf.psensornull); // do not use abs(), it would induce implicit cast to uint and overrun
//haydent capture milli amperage reading for minimosd via serial
amperage = (uint16_t)(powerValue * conf.pint2ma);
//haydent capture milli amperage reading for minimosd via serial
if ( powerValue < 333) { // only accept reasonable values. 333 is empirical
#ifdef LCD_TELEMETRY
if (powerValue > powerMax) powerMax = powerValue;
Then in the Serial Tab, near line 385:
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case MSP_ANALOG:
headSerialReply(7);//haydent
serialize8(vbat);
serialize16(intPowerMeterSum);
serialize16(rssi);
serialize16(amperage);//haydent
break;
Now finally in the MinimOSD sketch in the Serial Tab:
Near Line 149, make it look like this:
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if (cmdMSP==MSP_ANALOG)
{
MwVBat=read8();
pMeterSum=read16();
MwRssi = read16();
amperage = read16() / 100;//haydent - comes through as milliamps
}
also you will need to edit the minim osd config settings , there is something in there about power amperage factor, that it divides your amperage by. so set it to 1
That's it, enjoy !