VIP Suite Scaler; Bad Status Value and Strange Mixer Behaviour

Here is some C to start the vip blocks:

IOWR( LED_BASE, 0, 0x7 ); // All on

IOWR( SCALER_BASE, CONTROL, VIP_STOP );

IOWR( SCALER_BASE, SCALER_REG_SIZE_X, x_size );

IOWR( SCALER_BASE, SCALER_REG_SIZE_Y, y_size );

IOWR( SCALER_BASE, CONTROL, VIP_GO );

IOWR( TESTPAT_BASE, CONTROL, VIP_STOP );

IOWR( TESTPAT_BASE, TPG_REG_SIZE_X, x_size );

IOWR( TESTPAT_BASE, TPG_REG_SIZE_Y, y_size );

IOWR( TESTPAT_BASE, CONTROL, VIP_GO );

IOWR( MIXER_BASE, CONTROL, VIP_STOP );

IOWR( MIXER_BASE, MIXER_REG_LAYER1_X, x_pos );

IOWR( MIXER_BASE, MIXER_REG_LAYER1_Y, y_pos );

IOWR( MIXER_BASE, MIXER_REG_LAYER2_X, 0 );

IOWR( MIXER_BASE, MIXER_REG_LAYER2_Y, 0 );

IOWR( MIXER_BASE, MIXER_REG_LAYER1_ENABLE, VIP_CONSUME );

IOWR( MIXER_BASE, MIXER_REG_LAYER2_ENABLE, VIP_GO );

IOWR( MIXER_BASE, CONTROL, VIP_GO );

I'm using this code to read back the registers through the jtag uart:

alt_printf( "\nScaler Registers:\n" );

alt_printf( " Status: %x\n", IORD( SCALER_BASE, STATUS ) );

alt_printf( " Size X: %x\n", IORD( SCALER_BASE, SCALER_REG_SIZE_X ) );

alt_printf( " Size Y: %x\n", IORD( SCALER_BASE, SCALER_REG_SIZE_Y ) );

alt_printf( "\nMixer Registers:\n" );

alt_printf( " Status: %x\n", IORD( MIXER_BASE, MIXER_REG_STATUS ) );

alt_printf( " L1 X: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER1_X ) );

alt_printf( " L1 Y: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER1_Y ) );

alt_printf( " L1 Enable: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER1_ENABLE ) );

alt_printf( " L2 X: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER2_X ) );

alt_printf( " L2 Y: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER2_Y ) );

alt_printf( " L2 Enable: %x\n", IORD( MIXER_BASE, MIXER_REG_LAYER2_ENABLE ) );//