[[jcarteagaf]]

Prueba cambiando tu query de esta forma

Código SQL [-]
SELECT DISTINCT 
  dbo.PM20000.VENDORID,
  dbo.PM00200.VENDNAME,
  SALDO = SUM( CASE WHEN(dbo.PM20000.DOCTYPE <> 6 AND dbo.PM20000.DOCTYPE <> 5) THEN dbo.PM20000.CURTRXAM ELSE 0 END) AS FIELD_1,
  SALDO1 = SUM(CASE WHEN(dbo.PM20000.DOCTYPE = 6 AND dbo.PM20000.DOCTYPE = 5) THEN 0 ELSE SUM(dbo.PM20000.CURTRXAM) *-1 END) AS FIELD_2
FROM
  dbo.PM20000
  INNER JOIN dbo.PM00200 ON (dbo.PM20000.VENDORID = dbo.PM00200.VENDORID)
GROUP BY
  dbo.PM20000.VENDORID,
  dbo.PM00200.VENDNAME,
  dbo.PM20000.DOCTYPE