Change hashCode and equals to use all fields. Older format of ork files did not include digest so that is not enough to compare placeholders.

core/src/net/sf/openrocket/motor/ThrustCurveMotorPlaceholder.java

@@ -112,7 +112,23 @@ public class ThrustCurveMotorPlaceholder implements Motor {
 	public int hashCode() {
 		final int prime = 31;
 		int result = 1;
+		long temp;
+		temp = Double.doubleToLongBits(delay);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result
+				+ ((designation == null) ? 0 : designation.hashCode());
+		temp = Double.doubleToLongBits(diameter);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
 		result = prime * result + ((digest == null) ? 0 : digest.hashCode());
+		temp = Double.doubleToLongBits(emptyMass);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		temp = Double.doubleToLongBits(launchMass);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		temp = Double.doubleToLongBits(length);
+		result = prime * result + (int) (temp ^ (temp >>> 32));
+		result = prime * result
+				+ ((manufacturer == null) ? 0 : manufacturer.hashCode());
+		result = prime * result + ((type == null) ? 0 : type.hashCode());
 		return result;
 	}
 
@@ -125,14 +141,42 @@ public class ThrustCurveMotorPlaceholder implements Motor {
 		if (getClass() != obj.getClass())
 			return false;
 		ThrustCurveMotorPlaceholder other = (ThrustCurveMotorPlaceholder) obj;
+		if (Double.doubleToLongBits(delay) != Double
+				.doubleToLongBits(other.delay))
+			return false;
+		if (designation == null) {
+			if (other.designation != null)
+				return false;
+		} else if (!designation.equals(other.designation))
+			return false;
+		if (Double.doubleToLongBits(diameter) != Double
+				.doubleToLongBits(other.diameter))
+			return false;
 		if (digest == null) {
 			if (other.digest != null)
 				return false;
 		} else if (!digest.equals(other.digest))
 			return false;
+		if (Double.doubleToLongBits(emptyMass) != Double
+				.doubleToLongBits(other.emptyMass))
+			return false;
+		if (Double.doubleToLongBits(launchMass) != Double
+				.doubleToLongBits(other.launchMass))
+			return false;
+		if (Double.doubleToLongBits(length) != Double
+				.doubleToLongBits(other.length))
+			return false;
+		if (manufacturer == null) {
+			if (other.manufacturer != null)
+				return false;
+		} else if (!manufacturer.equals(other.manufacturer))
+			return false;
+		if (type != other.type)
+			return false;
 		return true;
 	}
 
+
 	@Override
 	public String toString() {
 		return "ThrustCurveMotorPlaceholder [manufacturer=" + manufacturer