The error of GPU Registration

Dear author,
For GPU Registration, there are some questions as following:
1. Can we implement Rigid Registration in GPU environment?
2. Do you have the example of GPU Rigid Registration?
3. For the same data and parameter , 'itkCPUDemons' will run correctly, but 'itkGPUDemons' will print the error as following.
Look forward to your reply!

Available tests:
0. itkGPUDemonsRegistrationFilterTest
1. itkGPUDemonsRegistrationFilterTest2
To run a test, enter the test number: 0
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Starting GPU Demons
Platform : NVIDIA CUDA
GeForce RTX 2080 SUPER
Maximum Work Item Sizes : { 1024, 1024, 64 }
Maximum Work Group Size : 1024
Alignment in bits of the base address : 4096
Smallest alignment in bytes for any data type : 128
cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_fp64 cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_d3d10_sharing cl_khr_d3d10_sharing cl_nv_d3d11_sharing cl_nv_copy_opts cl_nv_create_buffer cl_khr_int64_base_atomics cl_khr_int64_extended_atomics
Defines: #define DIM_3
#define BUFPIXELTYPE float
#define OUTPIXELTYPE float
#define PIXELDIM 3

Defines: #define DIM_3
#define OUTPIXELTYPE float

Defines: #define DIM_3
#define IMGPIXELTYPE float
#define BUFPIXELTYPE float
#define OUTPIXELTYPE float

Defines: #define blockSize 128
#define nIsPow2 0
#define T int

Defines: #define blockSize 128
#define nIsPow2 0
#define T float

Defines: #define blockSize 128
#define nIsPow2 0
#define T float

Debug: In D:\code\ITK\GPU\ITK-5.0.1\Modules\Registration\GPUPDEDeformable\test\itkGPUDemonsRegistrationFilterTest.cxx, line 66
Object (0000006DA43DECE0): Progress: 0 Iter: 0 Metric: 1.79769e+308 RMSChange: 0

Debug: In D:\code\ITK\GPU\ITK-5.0.1\Modules\Registration\GPUPDEDeformable\test\itkGPUDemonsRegistrationFilterTest.cxx, line 66
Object (0000006DA43DECE0): Progress: 0.001 Iter: 1 Metric: 5.37888e+08 RMSChange: 0.330045

GPU InitTime in seconds = 0.591444
GPU ComputeUpdateTime in seconds = 0.0272989
GPU ApplyUpdateTime in seconds = 0.000747204
GPU SmoothFieldTime in seconds = 0.0613015
Debug: In D:\code\ITK\GPU\ITK-5.0.1\Modules\Core\Common\src\itkObject.cxx, line 609
Object (0000006DA43DECE0): Destructing!

WARNING: In D:\code\ITK\GPU\ITK-5.0.1\Modules\Core\Common\src\itkLightObject.cxx, line 206
LightObject (0000006DA43DECE0): Trying to delete object with non-zero reference count.

Finished GPU Demons
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