Crash on using MDLImport

UE4 crashing on importing mdl file (i’ve got same crash on latest sources from git):

Assertion failed: Inputs[0].ExpressionData.Expression->IsA<UMaterialExpressionScalarParameter>() && (MDLType.get_kind() == mi::neuraylib::IType::TK_INT) [File:D:/Build/++UE4/Sync/Engine/Plugins/Enterprise/MDLImporter/Source/MDLImporter/Private/generator/MaterialExpressionFactory.cpp] [Line: 266]

MDL context:

    export material add_top_coat(
    	material base = material(),
    	uniform bool surface_top_coat_enable = true,
    	uniform bool backface_top_coat_enable = false,
    	color top_coat_color = color(1.),
    	float top_coat_weight = 1.0,
    	float top_coat_roughness = 0.0,
    	uniform int top_coat_color_transmit_enable = 0,
    
    	uniform top_coat_weighting top_coat_layer_mode = tcw_principled_specular,
    	//Fresnel Curve
    	float top_coat_fresnel_curve_ior = 1.5,
    
    	//Custom Curve
    	float top_coat_custom_curve_normal = 0.04,
    	float top_coat_custom_curve_grazing = 1.0,
    	float top_coat_custom_curve_exponent = 5.0,
    
    	//PBR Specular Curve
    	float top_coat_curve_strength = 0.04,
    
    	//Directional color
    	uniform bool top_coat_directional_color_enable = false,
    	color top_coat_directional_normal_color = color(1.),
    	color top_coat_directional_grazing_color = color(1.),
    
    	//Anisotropy
    	uniform bool top_coat_anisotropy_enable = true,
    	float top_coat_anisotropy = 0,
    	float top_coat_anisotropy_rotation = 0,
    	float3 top_coat_bump = state::normal(),	
    	uniform distribution_function_mode df_mode = dfm_glossy
    ) = let {
    
    	base::anisotropy_return top_coat_aniso = base::anisotropy_conversion(
    		roughness: top_coat_roughness,
    		anisotropy: top_coat_anisotropy_enable ? top_coat_anisotropy : 0,
    		anisotropy_rotation: top_coat_anisotropy_enable ? top_coat_anisotropy_rotation : 0
    	);
    
    	uniform bool top_coat_color_is_scatter_and_transmit_enabled = is_scatter_and_transmit_enabled(top_coat_color_transmit_enable);
    	base::texture_return calc_top_coat_val = top_coat_color_is_scatter_and_transmit_enabled ?
    		transmit_color_calc( top_coat_color, top_coat_weight, is_scatter_and_transmit_intensity(top_coat_color_transmit_enable) ) : base::texture_return();
    
    	color glossy_bsdf_tint = top_coat_color_is_scatter_and_transmit_enabled ? calc_top_coat_val.tint : top_coat_color;
    	float glossy_bsdf_weight = top_coat_color_is_scatter_and_transmit_enabled ? calc_top_coat_val.mono : top_coat_weight;
    
    	bsdf base_glossy = choose_bsdf(
    		df_mode : df_mode,
    		mode: df::scatter_reflect,
    		tint: glossy_bsdf_tint,
    		roughness_u: top_coat_aniso.roughness_u,
    		roughness_v: top_coat_aniso.roughness_v,
    		tangent_u: top_coat_aniso.tangent_u
    	).surface.scattering;
    
    	
    	bsdf full_glossy = top_coat_directional_color_enable ? df::directional_factor(
    		normal_tint: top_coat_directional_normal_color,
    		grazing_tint: top_coat_directional_grazing_color,
    		exponent: (top_coat_layer_mode==tcw_principled_specular) ? 5.f : top_coat_custom_curve_exponent,
    		base:  base_glossy
    	) : base_glossy;
    
    	bsdf surface_top_coat_coating = surface_top_coat_enable ?
    			(
    				( top_coat_layer_mode==tcw_principled_specular || top_coat_layer_mode==tcw_custom_curve )?
    				df::custom_curve_layer(
    					normal_reflectivity: (top_coat_layer_mode==tcw_principled_specular) ?
    						(top_coat_curve_strength)
    						: top_coat_custom_curve_normal,
    					grazing_reflectivity: (top_coat_layer_mode==tcw_principled_specular) ? 1.f : top_coat_custom_curve_grazing,
    					exponent: (top_coat_layer_mode==tcw_principled_specular) ? 5.f : top_coat_custom_curve_exponent,
    					weight: glossy_bsdf_weight,
    					layer: full_glossy,
    					base: base.surface.scattering,
    					normal: top_coat_bump
    				)
    				:
    				(
    					( top_coat_layer_mode==tcw_fresnel ) ?
    					df::fresnel_layer(
    						ior: color(top_coat_fresnel_curve_ior),
    						weight: glossy_bsdf_weight,
    						layer: full_glossy,
    						base: base.surface.scattering,
    						normal: top_coat_bump
    					)
    					:
    					df::weighted_layer(					
    						weight: glossy_bsdf_weight,
    						layer: full_glossy,
    						base: base.surface.scattering,
    						normal: top_coat_bump
    					)
    				)
    			)
    			: bsdf();
    
    	bsdf backface_top_coat_coating = backface_top_coat_enable ?
    			(
    				( top_coat_layer_mode==tcw_principled_specular || top_coat_layer_mode==tcw_custom_curve )?
    				df::custom_curve_layer(
    					normal_reflectivity: (top_coat_layer_mode==tcw_principled_specular) ?
    						(top_coat_curve_strength)
    						: top_coat_custom_curve_normal,
    					grazing_reflectivity: (top_coat_layer_mode==tcw_principled_specular) ? 1.f : top_coat_custom_curve_grazing,
    					exponent: (top_coat_layer_mode==tcw_principled_specular) ? 5.f : top_coat_custom_curve_exponent,
    					weight: glossy_bsdf_weight,
    					layer: full_glossy,
    					base: base.backface.scattering,
    					normal: top_coat_bump
    				)
    				:
    				(
    					( top_coat_layer_mode==tcw_fresnel ) ?
    					df::fresnel_layer(
    						ior: color(top_coat_fresnel_curve_ior),
    						weight: glossy_bsdf_weight,
    						layer: full_glossy,
    						base: base.backface.scattering,
    						normal: top_coat_bump
    					)
    					:
    					df::weighted_layer(					
    						weight: glossy_bsdf_weight,
    						layer: full_glossy,
    						base: base.backface.scattering,
    						normal: top_coat_bump
    					)
    				)
    			)
    			: bsdf();
    } in
    material(
    	thin_walled: base.thin_walled,
    	surface : surface_top_coat_enable ?
    		material_surface(
    			emission : base.surface.emission,
    			scattering : surface_top_coat_coating
    		)
    		:
    		base.surface,
    	backface : backface_top_coat_enable ?
    		material_surface(
    			emission : base.backface.emission,
    			scattering : backface_top_coat_coating
    		)
    		:
    		base.backface,
    	ior: base.ior,
    	volume : base.volume,
    	geometry : base.geometry
    );

same crash in 4.24.2

same crash in 4.25
i understand that MDL Import crashed on line like this, when arguments in operator ? are enums
mode: refraction_reflection_enable ? df::scatter_reflect_transmit : df::scatter_transmit