Whether an appeal to the supervisory authority is admissible against the refusal to grant suspensive effect in debt enforcement complaint proceedings.
No; the refusal to grant suspensive effect is a purely procedural measure and not an act of enforcement, so the LP and cantonal procedure provide no appeal against it.
A complaint to the supervisory authority may target only a measure or decision of an enforcement organ. Granting, refusing, or withdrawing suspensive effect is procedural only, not enforcement. Neither federal debt enforcement law nor Vaud implementing law provides such a remedy, and the CPC does not apply to complaint proceedings.