diff --git a/packages/SimulationStudio-Sandbox.package/Sandbox2.class/instance/context.doNamedPrimitiveIn.for.withArgs..st b/packages/SimulationStudio-Sandbox.package/Sandbox2.class/instance/context.doNamedPrimitiveIn.for.withArgs..st
index 1d567ba..6140649 100644
--- a/packages/SimulationStudio-Sandbox.package/Sandbox2.class/instance/context.doNamedPrimitiveIn.for.withArgs..st
+++ b/packages/SimulationStudio-Sandbox.package/Sandbox2.class/instance/context.doNamedPrimitiveIn.for.withArgs..st
@@ -30,12 +30,19 @@ context: aContext doNamedPrimitiveIn: aCompiledMethod for: rcvr withArgs: argume
 					writableObject]].
 			[#CroquetPlugin] -> ["allowed"].
 			[#FilePlugin] -> [^ self context: aContext activateOperationForbidden: 'FilePlugin not available in simulation'].
+				"[((aContext object: (self writableObjectFor: rcvr) eqeq: rcvr) ""hasOwnObject"" and:
+					[(#(primitiveFileGetPosition primitiveFileSetPosition primitiveFileRead) includes: primitiveName) or: [(rcvr isKindOf: StandardFileStream) and: [[rcvr isReadOnly] ifError: [false]] and: [#(primitiveFileFlush) includes: primitiveName]]])
+						ifFalse: [^ self context: aContext activateOperationForbidden: ('FilePlugin not available in simulation except for read-only accesses to own objects ({1})' format: {primitiveName})]]."
 			[#FloatArrayPlugin] -> [^ self context: aContext primitiveFailTokenFor: nil "use image implementation"].
 			[#Float64ArrayPlugin] -> [^ self context: aContext primitiveFailTokenFor: nil "use image implementation"].
 			[#LargeIntegers] -> ["allowed"].
 			[#MiscPrimitivePlugin] -> [^ self context: aContext primitiveFailTokenFor: nil "use image implementation"].
 			[#SimulationStudio] -> ["allowed"].
 			[#UUIDPlugin] -> ["allowed"].
+			[#ZipPlugin] -> [
+				(#('primitiveUpdateGZipCrc32' 'primitiveUpdateAdler32') includes: primitiveName)
+					ifTrue: ["allowed"]
+					ifFalse: ["use image implementation" self context: aContext primitiveFailTokenFor: nil] ].
 			[nil] -> [
 				(#('primitiveHighResClock' 'primitiveUtcWithOffset' 'primitiveUtcWithOffset') includes: primitiveName)
 					ifTrue: ["allowed"]
diff --git a/packages/SimulationStudio-Sandbox.package/Sandbox2.class/methodProperties.json b/packages/SimulationStudio-Sandbox.package/Sandbox2.class/methodProperties.json
index 0b863d9..a8056e8 100644
--- a/packages/SimulationStudio-Sandbox.package/Sandbox2.class/methodProperties.json
+++ b/packages/SimulationStudio-Sandbox.package/Sandbox2.class/methodProperties.json
@@ -14,7 +14,7 @@
 		"basicEvaluate:" : "ct 11/13/2021 16:12",
 		"context:activateOperationForbidden:" : "ct 11/13/2021 01:04",
 		"context:canBeImmutable:" : "ct 11/12/2021 23:54",
-		"context:doNamedPrimitiveIn:for:withArgs:" : "ct 5/2/2022 21:43",
+		"context:doNamedPrimitiveIn:for:withArgs:" : "ct 1/2/2025 22:59",
 		"context:doPrimitive:method:receiver:args:do:" : "ct 9/20/2022 13:10",
 		"context:doPrimitiveHash:receiver:args:" : "ct 11/12/2021 23:56",
 		"context:doPrimitiveNew:receiver:args:" : "ct 9/20/2022 13:07",
diff --git a/packages/SimulationStudio-Sandbox.package/SandboxContext.class/instance/doNamedPrimitiveIn.for.withArgs..st b/packages/SimulationStudio-Sandbox.package/SandboxContext.class/instance/doNamedPrimitiveIn.for.withArgs..st
index f8dcd87..c181083 100644
--- a/packages/SimulationStudio-Sandbox.package/SandboxContext.class/instance/doNamedPrimitiveIn.for.withArgs..st
+++ b/packages/SimulationStudio-Sandbox.package/SandboxContext.class/instance/doNamedPrimitiveIn.for.withArgs..st
@@ -30,12 +30,19 @@ doNamedPrimitiveIn: aCompiledMethod for: rcvr withArgs: arguments
 					writableObject]].
 			[#CroquetPlugin] -> ["allowed"].
 			[#FilePlugin] -> [^ self activateOperationForbidden: 'FilePlugin not available in simulation'].
+				"[((self object: (self sandbox writableObjectFor: rcvr) eqeq: rcvr) ""hasOwnObject"" and:
+					[(#(primitiveFileGetPosition primitiveFileSetPosition primitiveFileRead) includes: primitiveName) or: [(rcvr isKindOf: StandardFileStream) and: [[rcvr isReadOnly] ifError: [false]] and: [#(primitiveFileFlush) includes: primitiveName]]])
+						ifFalse: [^ self activateOperationForbidden: ('FilePlugin not available in simulation except for read-only accesses to own objects ({1})' format: {primitiveName})]]."
 			[#FloatArrayPlugin] -> ["allowed"].
 			[#Float64ArrayPlugin] -> ["allowed"].
 			[#LargeIntegers] -> ["allowed"].
 			[#MiscPrimitivePlugin] -> [^ self class primitiveFailTokenFor: nil "use image implementation"].
 			[#SimulationStudio] -> ["allowed"].
 			[#UUIDPlugin] -> ["allowed"].
+			[#ZipPlugin] -> [
+				(#('primitiveUpdateGZipCrc32' 'primitiveUpdateAdler32') includes: primitiveName)
+					ifTrue: ["allowed"]
+					ifFalse: [^ self activateOperationForbidden: ('Unknown primitive {1} not available in simulation' format: {primitiveName})] ].
 			[nil] -> [
 				(#('primitiveHighResClock' 'primitiveUtcWithOffset' 'primitiveUtcWithOffset') includes: primitiveName)
 					ifTrue: ["allowed"]
diff --git a/packages/SimulationStudio-Sandbox.package/SandboxContext.class/methodProperties.json b/packages/SimulationStudio-Sandbox.package/SandboxContext.class/methodProperties.json
index d6d5db7..961404d 100644
--- a/packages/SimulationStudio-Sandbox.package/SandboxContext.class/methodProperties.json
+++ b/packages/SimulationStudio-Sandbox.package/SandboxContext.class/methodProperties.json
@@ -5,7 +5,7 @@
 		"access:indirectors:" : "ct 3/20/2021 23:35",
 		"activateOperationForbidden:" : "ct 3/3/2021 17:55",
 		"canBeImmutable:" : "ct 3/22/2021 23:47",
-		"doNamedPrimitiveIn:for:withArgs:" : "ct 5/10/2022 16:24",
+		"doNamedPrimitiveIn:for:withArgs:" : "ct 1/2/2025 23:17",
 		"doPrimitive:method:receiver:args:" : "ct 9/20/2022 13:00",
 		"doPrimitiveHash:receiver:args:" : "ct 3/22/2021 18:51",
 		"doPrimitiveNew:receiver:args:" : "ct 9/20/2022 13:06",