The following practices are coming from several consultants:

GIT

• must be used by everybody on the project 
  • if customer is co-operating on the project, they must use it as well
• everybody commits their changes to GIT
• nobody does the changes directly to the partition (without committing to GIT as well)
• the actual version (of the configuration) from GIT can be deployed to the partition at any time

Such approach helps to avoid overrides and solve collisions.

Note: It would be good to have a Role to be able to see the logics in the ReadOnly mode.

Check of the Inputs (from User and Data tables) 

• if it is allowed to have missing or wrong values, then we can solve it by Alerts (Yellow, Red, Critical), eventually use api.abortCalculation()
• if configuration data is missing, and calculation does not make sense without them, we can use api.throwException()
• we can make additional field, which shows to the user the reasons for the Alert
• Sample

  def priceType = "CostPlus"
  
  def price = null
  def reason = "Unknown error"
  
  def targetMargin = api.getElement("TargetMargin")
  
  if (targetMargin) {
    def vat = api.getElement("VAT")
    def cost = api.getElement("Cost")
  
    if (cost && vat != null) {
        price = cost * targetMargin * (1 + vat)
        reason = "OK"
    } else {
      reason = "No Average or Calculated cost price in PX Cost_RRP or VAT defined"
      api.redAlert(reason)
    }
  } else {
    reason = "No target margin defined"
    api.redAlert(reason)
  }
  
  api.local.reason = reason
  
  return price